Demography and Health

MPH Ist Year

Demography and Health

Prabesh Ghimire


MPH 1st Year

Table of Contents UNIT 1: INTRODUCTION TO DEMOGRAPHY AND HEALTH ..................................................................... 4 Introduction to Demography: ................................................................................................................... 4 Population Pyramid................................................................................................................................... 5 Concept of Young and Old Population ...................................................................................................... 6 Aging of Population ................................................................................................................................... 7 Dependency Ratio ..................................................................................................................................... 8 UNIT 2: MEASURES OF FERTILITY, MORTALITY, MIGRATION, URBANIZATION AND NUPTIALITY ........... 8 UNIT 2.1: FERTILITY AND ITS MEASURES .............................................................................................. 8 Measures of fertility and reproduction: ................................................................................................... 8 Measures of Reproduction ................................................................................................................. 10 Replacement Level Fertility................................................................................................................. 10 Population Momentum....................................................................................................................... 10 Determinants of Fertility ......................................................................................................................... 11 Baby Boom and Baby Bust Syndrome ..................................................................................................... 12 UNIT 2.2: MORTALITY AND ITS MEASURES ......................................................................................... 13 Measures of Mortality ............................................................................................................................ 13 Determinants of Mortality ...................................................................................................................... 15 Standardization of Death Rates .............................................................................................................. 16 Life Table ................................................................................................................................................. 19 UNIT 2.3 MIGRATION AND ITS MEASURES ......................................................................................... 23 Basic Terminology of Migration .............................................................................................................. 23 Determinants of Migration ..................................................................................................................... 23 Measures of Migration............................................................................................................................ 24 Simple Measure to Calculate Internal Migration ................................................................................ 24 UNIT 2.4: NUPTIALITY AND ITS MEASURES ......................................................................................... 25 Basic Terminologies of Nuptiality ........................................................................................................... 25 Determinants of Nuptiality ..................................................................................................................... 26 Simple Measures of Nuptiality ................................................................................................................ 26 UNIT 2.5: URBANIZATION AND ITS MEASURES ................................................................................... 28 Basic Terminology of Urbanization ......................................................................................................... 28

©Prabesh Ghimire

Page | 2


MPH 1st Year

Measures of Urbanization....................................................................................................................... 29 UNIT 3: POPULATION ESTIMATES AND PROJECTIONS ......................................................................... 33 UNIT 4: POPULATION THEORIES AND POLICY ..................................................................................... 38 UNIT 4.1: POPULATION THEORIES ...................................................................................................... 38 Early Thinking on Population Issues........................................................................................................ 38 Malthusian Theory of Population: .......................................................................................................... 39 NEO-MALTHUSIANISM ............................................................................................................................ 40 Demographic Transition Theory ............................................................................................................. 41 UNIT 4.2: POPULATION POLICY .......................................................................................................... 43 Concept of Population Policy .................................................................................................................. 43 UNIT 5: HUMAN DEVELOPMENT INDEX .............................................................................................. 46 Concept of Human Development Index.................................................................................................. 46 Construction technique of HDI ............................................................................................................... 47 Current position of countries in HDI ....................................................................................................... 48 UNIT 6: POPULATION, ECOLOGY AND DEVELOPMENT ........................................................................ 48 Population Explosion and Its Effect in Ecology and Public Health .......................................................... 48 IMPORTANT FORMULA ...................................................................................................................... 50

©Prabesh Ghimire

Page | 3


MPH 1st Year

UNIT 1: INTRODUCTION TO DEMOGRAPHY AND HEALTH Introduction to Demography: Donald Bogue, in his book entitled “Principles of Demography” defines “demography as the statistical and mathematical study of the size, composition and spatial distribution of human population, and of changes over time in these aspects through the operation of the five processes of fertility, mortality, marriage, migration and social mobility. Sources of Demographic and health data Reliable, timely and relevant demographic data have been considered essential to develop, implement, monitor and evaluate the population and associated programmes. Sufficient data need to be made available at national, regional and local level to undertake research works and policy decisions concerning population and development. Basically demographic data in Nepal can be obtained from five different sources such as i. Population Censuses ii. Demographic Sample Surveys iii. Vital Registration iv. Population Registers v. Administrative Statistics/Official records i.

Population Census: United Nations (1958) defines census as “A census of Population May be defined as the total process of collecting compiling and publishing demographic economic and social data pertaining at a specified time or times to all persons in a country or delimited territory.” The most comprehensive and widespread demographic data for Nepal can be obtained from census which is conducted every ten years. The first population count in Nepal was carried out in the year 1911. Since then censuses in Nepal are being carried out at an interval of more or less ten years. Latest census of Nepal was carried out in 2011 which provides data on numerous demographic variables.

ii.

The Demographic and Sample Surveys A sample survey is cheaper and easier to administer than a census. It involves the selection of population who represent the whole population, or a particular sub-group of population. A sample can get more detailed and higher quality information than a census, because more time and effort can be spent on each interview. Some of the major demographic and sample surveys conducted in Nepal are SN Surveys Years conducted Organization 1 Nepal Demographic and Health Survey 2001, 2006, 2011 MOH(P) 2 Nepal Adolescent and Youth Survey 2010/11 MOHP 3 Nepal Living Standard Survey 1996, 2003, 2009 CBS 4 Nepal Family Health Survey 1996 MOHP Nepal Demographic Health and Survey is one of the most popular sample survey conducted in Nepal every five years. These surveys have provided reliable estimates of fertility, family planning, mortality and health indicators for Nepal.

©Prabesh Ghimire

Page | 4


MPH 1st Year

iii. Vital Registration Vital Statistics viz; data on births deaths, migration, marriages, and divorces etc; provide data on a continuous basis. Therefore these data are very useful in studying population dynamics over the years. The vital registration system in Nepal covers the following events  Birth  Deaths  Marriage  Migration and finally  Divorce In Nepal, Vital registration was launched in 2035 B.S and was gradually expanded to all the 75 districts of the country. This system is currently maintained by Ministry of Federal Affairs and Local Development. However due to various reasons /limitations & constraints, most of the vital events are not registered or even if they are registered, they are registered very late. Thus the data obtained from the vital registration system are not often used for demographic analysis. iv. Population Registers Another source of population data is Population Register, which provides a continuous record of changes in population movements. Population movements and changes therein are registered in population registers in an integrated manner. Basically the population registers are maintained for data on a) vital events b) Current estimate of the population both at the national and sub-national level and c) statistics on migratory movements. Although these registers provide useful data, this system is not maintained in Nepal. v.

Administrative Statistics/ Official Records: Population related data are also available through administrative records/official records. These records are maintained as part of the service delivery by the government. For example, the Family Health Division under Department of Health Services maintains data on number of sterilization performed under the mobile sterilization services. More detailed data on the health services delivered are available through the annual report of the Department of Health Services. In a likewise manner, the annual reports and different reports published by the Ministry of Education, other ministries and organizations including researchers are important sources of data related to population.

Population Pyramid A Population Pyramid is a graph that shows the age-sex distribution of a given population. It a graphic profile of the population’s residents. Sex is shown on the left/right sides, age on the y-axis, and the percentage of population on the x-axis. Each grouping (eg: males aged 0-4) is called a cohort. A population pyramid does not tell about the actual population in numbers. Rather, it displays percentages and shows what portion of people fall into each cohort. Public Health experts can use population pyramids to see population trends in the past, examine the current resident profile, and also to project how the population will increase/decrease in the future. This can provide valuable information for current and future health planning. Pyramids can be used in helping to predict changes in the age structure of the population over the next fifty or so years so that necessary health plans can be introduced to cope with the predicted demographic

©Prabesh Ghimire

Page | 5


MPH 1st Year

changes. For example, increase in female population of reproductive age may suggest increasing availability of reproductive health services including family planning measures. Types of Population Pyramid There are generally three types of population pyramids created from age-sex distributions--expansive, constrictive and stationary. i. Expansive - Expansive population pyramids show larger numbers or percentages of the population in the younger age groups. - These types of pyramids are usually found in populations with very large fertility rates and lower than average life expectancies. - The age-sex distributions of many Third World countries would probably display expansive population pyramids. ii. -

Constrictive Constrictive population pyramids display lower numbers or percentages of younger people. The age-sex distributions of the United States fall into this type of pyramid.

iii. Stationary - Stationary or near-stationary population pyramids display somewhat equal numbers or percentages for almost all age groups. - Of course, smaller figures are still to be expected at the oldest age groups. - The age-sex distributions of some European countries, especially Scandinavian ones, will tend to fall into this category.

Concept of Young and Old Population The age structure of a society is shaped by the processes of fertility, mortality and migration. A country may grow older or younger depending upon changes in the fertility rate, mortality rate, or the rate of migration. - When we refer to a population becoming younger or older, we are actually referring to the age distribution of a population, or the age-structure. - A population is considered to be young when there are proportionately more young people than people of other ages. A very popular measure of the youngness of a population is the percentage of population under 15 years of age. The high-fertility countries of Africa with large proportions of young adults and children are examples. -

It may be equally important to know something about the older part of a population. Currently, many European countries are concerned over the fact that the population is growing older.

©Prabesh Ghimire

Page | 6

Demography and Health -

-

-

-

MPH 1st Year

Normally we think of a population growing older when people live longer, but another factor that causes a population to age is declining fertility. The average age of a population will increase when fewer babies are being born, because there will be fewer young people to pull the average down. Conversely, when the fertility rate is high or increases, a population will become younger. Mortality changes also influence the age distribution of a population. However, under certain condition, death rate declines may actually cause a population to become younger. These two types of populations have markedly different age compositions; as a consequence, they also have different proportions of the population in the labor force or in school, as well as different medical needs, consumer preferences, and even crime patterns. A population’s age structure has a great deal to do with how that population lives. Developing countries have relatively young populations while most developed countries have old or “aging” populations. In many developing countries, 40 percent or more of the population is under age 15, while 4 percent is 65 or older. On the other hand, in virtually every developed country, less than 25 percent of the population is under age 15 and more than 10 percent is 65 or older. In Nepal, currently 34.9% population is in a younger age while 8.1% population is in the older age (60+ yrs) and 5.3% (in 65+ yrs). . This data shows that the country falls slightly towards the young population but is gradually aging.

Aging of Population In demographic studies, increase in the mean or median age of the population is called the ageing of the population. Aging of population (also known as population aging) is a summary term for shifts in the age distribution (i.e., age structure) of a population toward older ages. It is a natural outcome of demographic transition from high fertility and mortality to low fertility and mortality. Recently, worldwide population aging has been considered one of the most important demographic phenomena. It is the product of clear decreases in birth and mortality rates and an increase in life expectancy. the worldwide population aged 60 years and older will surpass from approximately 770 million in 2010 to an estimated one billion in 2020, and 20.0% of these people will be concentrated in developing countries. The number of people aged 65 years and above in Nepal was 1,397,583 according to the population census of 2011. This number accounts for 0.24% of old persons in the world and 5.27 % of Nepal’s population in 2011. In relation to the growing population, the volume of old persons is also increasing in Nepal in every successive census. In Nepal, recently ageing of population is an emerging social issue because fertility has started going down in recent years, the mortality is declining fast and the life expectancy is continuing to increase for both sexes in Nepal. According to the Nepal Demographic Health Survey 2011, the total fertility decreased to 2.6 from 3.1 in 2006. However, a continued increase in the percentage of aged persons in the population is creating humanitarian, social and economic problems in many less developed countries like Nepal. Past high fertility rates, combined with the decline in mortality has resulted in substantial growth in the number of old persons and, in conjunction with the subsequent fertility decline, to an increasing share of the elderly in the overall population.

©Prabesh Ghimire

Page | 7


SN

Census Year

1 2

2001 2011

Elderly Population growth rate 3.5

MPH 1st Year

Indices of Ageing (60+)

Percent of elderly (60+)

16.7 23.3

6.5 8.1

The increasing proportion of older persons compared to young person is called the ageing index. In 2011, the ageing index increased sharply and reached 23.3, higher for females than males. This might be due to the combined effects of declined fertility and mortality and a population shift from younger to old age. All age related indicators are in an increasing trend which suggests that the ageing of population is increasing Dependency Ratio The age-dependency ratio is the ratio of people in the “dependent” ages (those under age 15 and ages 60 and older) to those in the “economically productive” ages (15 to 60 years) in a population. The age-dependency ratio is often used as an indicator of the economic burden the productive portion of a population must carry—even though some people defined as “dependent” are producers and some people in the “productive” ages are economically dependent Countries with very high birth rates usually have the highest age-dependency ratios because of the large proportion of children in the population. The age-dependency ratio is sometimes divided into old-age dependency (the ratio of people ages 60 and older to those ages 15 to 60) and child dependency (the ratio of people under age 15 to those ages 15 to 60). Nepal’s dependency ratio in 2011 was 76 per 100, meaning that for every 100 persons in the working age population, 76 persons were dependents. The data from last two censuses show that child dependency is decreasing while old dependency is increasing in Nepal. UNIT 2: MEASURES OF FERTILITY, MORTALITY, MIGRATION, URBANIZATION AND NUPTIALITY UNIT 2.1: FERTILITY AND ITS MEASURES Fertility refers to the number of live births women have. Fertility is one of the main factors in determining the age structure of a population. The study of fertility is complex because it is affected by host factors including biological as well as behavioral Measures of fertility and reproduction: i. -

-

Crude Birth Rate: The Crude Birth Rate (CBR) indicates the number of live births per 1,000 mid-year total population in a given year. The Crude Birth Rate of Nepal is 24.3 births per 1000 mid-year population (2011) 𝐶𝐶𝐶𝐶𝐶𝐶 =

𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏ℎ𝑠𝑠 × 1000 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 𝑀𝑀𝑀𝑀𝑀𝑀 − 𝑌𝑌𝑌𝑌𝑌𝑌𝑌𝑌 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃

Crude death rate is affected by age structure of the population

©Prabesh Ghimire

Page | 8


ii. -

MPH 1st Year

Child Women Ratio: Child Woman ratio is one of the proxy indicators of fertility levels. This ratio is particularly useful in a country where there is no fertility related information either from censuses/surveys or a vital registration system. This ratio is normally calculated by dividing the total observed number of children below five years by the number of women aged 15 to 49 years. The child women ration of Nepal is 0.36 in 2011 which declined from 0.49 in 2011. 𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑐𝑐ℎ𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖 𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢 𝑎𝑎𝑎𝑎𝑎𝑎 5 𝐶𝐶𝐶𝐶𝐶𝐶 = 𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 15 − 49

iii. General Fertility Rate: - The general fertility rate (also called the fertility rate) is the number of live births per 1,000 women ages 15 to 49 in a given year. - The general fertility rate is a somewhat more refined measure than the birth rate because it relates births to the age-sex group at risk of giving birth (usually defined as women ages 15 to 49). This limitation helps eradicate distortions that might arise because of different age and sex distributions among populations. - Thus, the general fertility rate is a better basis to compare fertility levels among populations than are changes in the crude birth rate. 𝐺𝐺𝐺𝐺𝐺𝐺 =

𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏ℎ𝑠𝑠/ 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 × 1000 𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 15 − 49

iv. Age Specific Fertility Rate (ASFR) - The general fertility rate is not a very effective refinement of crude birth rate. It loses sight of the fact that fecundity of women changes during the span of the child bearing period. Therefore further refinement of fertility measured leads to the development of Age Specific Fertility Rate 𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏ℎ𝑠𝑠 𝑡𝑡𝑡𝑡 𝑚𝑚𝑚𝑚𝑚𝑚ℎ𝑒𝑒𝑒𝑒 𝑜𝑜𝑜𝑜 𝑎𝑎 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 𝑖𝑖𝑖𝑖 𝑡𝑡ℎ𝑒𝑒 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴 = × 1000 𝑚𝑚𝑚𝑚𝑚𝑚 − 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 𝑓𝑓𝑓𝑓𝑓𝑓𝑓𝑓𝑓𝑓𝑓𝑓 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝑖𝑖𝑖𝑖 𝑡𝑡ℎ𝑒𝑒 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 -

Age specific fertility rates are not affected by variations in age structure.

v. -

Total Fertility Rate (TFR) The total fertility rate (TFR) is the average number of children that would be born to a woman by the time she ended childbearing if she were to pass through all her childbearing years conforming to the age specific fertility rates of a given year. The TFR is one of the most useful indicators of fertility because it gives the best picture of how many children women are currently having. Total fertility rate is the sum of the age specific fertility rates of women in each five-year age group from 15 to 49 years. This is computed by dividing the number of births with the number of women multiplied by 1,000. The TFR is a synthetic measure; no individual woman is very likely to pass through three decades conforming to the age-specific fertility rates of any single year. The Total Fertility Rate of Nepal is 2.6 (NDHS,2011)

-

𝑇𝑇𝑇𝑇𝑇𝑇 =

©Prabesh Ghimire

∑7𝑖𝑖=0 ASFR ∗ age interval 1000

Page | 9


MPH 1st Year

Measures of Reproduction i. Gross Reproduction Rate (GRR) - The gross reproduction rate (GRR) is the average number of daughters that would be born to a woman (or group of women) during her lifetime if she passed through her childbearing years conforming to the age-specific fertility rates of a given year. - This rate is like the TFR except that it counts only daughters and literally measures “reproduction”—a woman reproducing herself by having a daughter. GRR = TFR * proportion of female births GRR = TFR * (female births/ total births) ii. -

-

Net Reproduction Rate (NRR) The net reproduction rate (NRR) is the average number of daughters that would be born to a woman (or group of women) if she passed from birth to the rest of her life conforming to the age-specific fertility and mortality rates of a given year. This rate is like the GRR, but it is always lower because it takes into account the fact that some women will die before completing their childbearing years.

Where, S= Survival rate

𝑁𝑁𝑁𝑁𝑁𝑁 =

7

5 �𝑖𝑖=0(ASFR × S) 1000

Replacement Level Fertility - Replacement-level fertility is the level of fertility at which women in the same cohort have exactly enough daughters (on average) to “replace” themselves in the population. A NRR of 1.00 is equal to replacement level. - Once replacement-level fertility has been reached and remains there, births will gradually reach equilibrium with deaths, and in the absence of immigration and emigration, a population ultimately will stop growing and become stationary in both size and age structure. The time this process takes varies greatly depending upon the current age structure of the population. - Today, virtually all developed countries are at or below replacement-level fertility. - The TFR can also be used to indicate replacement-level fertility by showing the average number of children sufficient to replace both parents in the population. In developed countries today, a TFR of about 2.1 is considered to be replacement level. - Replacement-level TFRs higher than 2.0 (one child for each parent) are needed because there are slightly more males than females born and not all females survive to their childbearing years. In developing countries with much higher mortality rates, TFRs of more than 2.1 result in replacementlevel fertility. Population Momentum - Population momentum refers to the tendency of a population to continue to grow after replacementlevel fertility has been achieved. - A population that has achieved replacement or below-replacement fertility may still continue to grow for some decades because past high fertility leads to a high concentration of people in the youngest ages. Total births continue to exceed total deaths as these youths become parents. Eventually, this large group becomes elderly and deaths increase to equal the number of births or outnumber them. Thus it may take two or three generations (50 to 70 years) before each new birth is offset by a death in the population. - Population momentum represents natural increase to the population.

©Prabesh Ghimire

Page | 10


MPH 1st Year

Determinants of Fertility The various factors affecting fertility includes: 1. Age at Marriage: - Age at marriage is an important determinant of total fertility. - There is a direct relationship between age at marriage and fertility- the lower age at marriage, the longer is the fertility period or the fertility span, and the higher is the fertility. - Conversely, the higher the age at marriage, the shorter is the fertility span and the fertility rate decreases. - More than half of young girls are married off by the age of 18 years in all rural areas and most urban areas of Nepal. The median age at Marriage for females in Nepal was 18 years in 2011. 2. Fecundity - It refers to the capacity to reproduce children. The genetic fertility of women is an important biological factor. 3. Sterility - Both men and women are responsible for lower fertility. - The lower the proportion of sterility, the higher is the rate of fertility. 4. Age at first birth - The onset of childbearing at an early age lengthens the reproductive period, thereby increasing the level of fertility. - The median age of first birth is 20.1 years. 5. -

Intervals between birth (spacing): Birth interval is the length of time between two successive live births. Information on birth intervals provides insight into birth spacing patterns, which affect fertility. The median birth interval in Nepal is 36.2 months.

6. Postpartum Amenorrhea, abstinence and insusceptibility: - Postpartum amenorrhea is the interval between the birth of a child and the resumption of menstruation, a period during which the risk of pregnancy is much reduced thereby reducing the fertility. - Postpartum protection from conception depends upon the intensity and duration of breastfeeding. Postpartum abstinence refers to the period of voluntary sexual inactivity after childbirth. - A woman is considered insusceptible if she is not exposed to the risk of pregnancy, either because she is amenorrheic or because she is abstaining from sexual intercourse following a birth. - Nepalese women are amenorrheic for a median of 6.6 months, abstain for a median of 3.0 months, and are insusceptible to pregnancy for a median of 8.2 months. 7. Menopause: - The risk of becoming pregnant declines with age. - The term infecundity refers to a process rather than a well-defined event, and although the onset of infecundity is difficult to determine for an individual woman, there are ways of estimating it for a group of women. - NDHS, 2011 of Nepal shows decreasing exposure to the risk of pregnancy (infecundity) for women age 30 or above.

©Prabesh Ghimire

Page | 11


8. 9. 10. 11. 12. 13. 14. 15. 16.

MPH 1st Year

Education Proportion of married women or in union Percentage of women breastfeeding exclusively Universality of marriage Duration of married life Less available health care Contraceptive use Economic status High infant mortality

Baby Boom and Baby Bust Syndrome Baby Boom Syndrome - The term baby boom syndrome is used to identify a massive and unprecedented increase in birth following world war II. - The period following world war II from 1946-1964 was marked by a dramatic increase in fertility rates and in the absolute number of births in countries (United States, Canada, Australia, New Zealand) who participated in world war II. - Baby boomers are those persons born worldwide between 1946 and 1964. - During this period of baby boom, approximately 79 million babies were born in US alone. Impacts of Baby Boom - After WWII, returning military personnel faced a severe housing shortage - In response to the crisis, developers used assembly-line methods to mass produce houses. Suburbs were born. - Men were expected to work, while women were expected to stay home and care for the children. - Divorce rates surged. - Baby boomers filled the job market making it difficult for next cohort (Baby Bust) to find jobs. - Increase loads to health care, social services and pension plans. Causes of baby boom syndrome i. Catch up fertility - The fertility went up after the war because marriages and pregnancies that had been postponed during wartime or during the economic depression were taken up again. ii. -

Role of marriage Rising marriage rates during the baby boom era was a key factor behind the rise of period fertility. Decline in average age at marriage contributed to a rise of total marital fertility.

iii. Demobilization of military personnel iv. Relative wage of women - It is argued that during the baby boom period, the relative wages of women were low and this lowered the opportunity costs of having children. At the same time, the wages of husbands were rising. This generated a positive income effect on fertility.

©Prabesh Ghimire

Page | 12


MPH 1st Year

Baby Bust Syndrome - The period immediately after the baby boom from late 1960’s and early 1970’s marked by a rapid sudden decline in the fertility rates is termed as baby bust syndrome. Causes of baby bust syndrome - High divorce rate - Increase in the proportion of never married - Increase in illegitimate fertility - Development of concept of equal status of women - Increase in abortion rate - Development of science and technology - Increase in female wages and income; women entered the workforce UNIT 2.2: MORTALITY AND ITS MEASURES Measures of Mortality Various measure of Mortality Includes i. Crude Death Rate ii. Age Specific Death Rate iii. Under-5 Mortality Rate- 54 per 1000 live birth iv. Infant Mortality Rate- 46 per 1000 live births v. Neonatal Mortality Rate (0 -28 days) – 33 per 1000 live births a. Early Neonatal Mortality Rate (0-7 days) b. Late Neonatal Mortality Rate (8-28 days) vi. Post Neonatal Mortality Rate (29 days to 1 yr) vii. Perinatal Mortality Rate (still birth+ early neonate)- 37 per 1000 pregnancies i.

ii. -

Crude Death Rate: The Crude Death Rate (CBR) indicates the number of deaths per 1,000 mid-year total population in a given year. 𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑓𝑓 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑ℎℎ𝑠𝑠 𝐶𝐶𝐶𝐶𝐶𝐶 = × 1000 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 𝑀𝑀𝑀𝑀𝑀𝑀 − 𝑌𝑌𝑌𝑌𝑌𝑌𝑌𝑌 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃 Crude death rate is affected by age structure of the population.

Age Specific Death Rate (ASDR) The age specific fertility rate is defined as the number of deaths per year in a specific age group per 1000 persons in the same age-group 𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑ℎ𝑠𝑠 𝑖𝑖𝑖𝑖 𝑎𝑎 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 𝑖𝑖𝑖𝑖 𝑡𝑡ℎ𝑒𝑒 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴 = × 1000 𝑚𝑚𝑚𝑚𝑚𝑚 − 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝑖𝑖𝑖𝑖 𝑡𝑡ℎ𝑒𝑒 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔

Advantages - Age specific fertility rates are not affected by variations in age structure. - Can compare mortality at different ages - Can compare mortality in the same age groups over time and/or between countries and areas. - Can be used to calculate life tables to create an age-independent measure of mortality (lifeexpectancy)

©Prabesh Ghimire

Page | 13


MPH 1st Year

iii. Cause specific death rate - Cause specific death rates are deaths attributable to particular cause per 10,000 or 100,000 total number of deaths. iv. Infant Mortality Rate (IMR) - Number of deaths of infants under age 1 per year per 1000 live births in the same year. (𝑁𝑁𝑁𝑁. 𝑜𝑜𝑜𝑜 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑ℎ𝑠𝑠 𝑜𝑜𝑜𝑜 𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖 𝑖𝑖𝑖𝑖 𝑎𝑎 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦) 𝐼𝐼𝐼𝐼𝐼𝐼 = × 1000 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏ℎ𝑠𝑠 𝑖𝑖𝑖𝑖 𝑡𝑡ℎ𝑒𝑒 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 - Infant Mortality of Nepal in 46 per 1000 live births (NDHS, 2011) Why infant mortality rate? - IMR is a good indicator of the overall health status of a population. - It is a major determinant of life expectancy at birth - IMR is sensitive to levels and changes in socio-economic conditions of a population. Factors affecting IMR of a country Endogenous Factor - Age of Mother - Birth order of the child - Parity - Birth Intervals - Weight at birth - Multiple birth - Premature birth

v. -

Exogenous Factors - Nutrition of mother and infants - Infections and disease (malaria, measles, diarrhoea, pneumonia, etc.) - Adverse environmental conditions (congestion, lack of sanitation and safe drinking water) - Availability of health services • Immunization • Diarrhoea control • ARI control - Socio-economic status - Maternal literacy

Neonatal Mortality Rate (NMR) Deaths of neonates (upto 28 days of life) per 1000 live births. NMR of Nepal is 33 deaths per 1,000 live births. 𝑁𝑁𝑁𝑁𝑁𝑁 =

(𝑁𝑁𝑁𝑁. 𝑜𝑜𝑜𝑜 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑ℎ𝑠𝑠 𝑜𝑜𝑜𝑜 𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛 (0 − 28 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑) 𝑖𝑖𝑖𝑖 𝑎𝑎 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦) × 1000 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏ℎ𝑠𝑠 𝑖𝑖𝑖𝑖 𝑡𝑡ℎ𝑒𝑒 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦

vi. Maternal Mortality Ratio - Number of women who die as a result of complications of pregnancy or childbearing in a given year per 100,000 live births in that year. - MMR represents the risk associated with pregnancy.

𝑀𝑀𝑀𝑀𝑀𝑀 =

©Prabesh Ghimire

(𝑁𝑁𝑁𝑁. 𝑜𝑜𝑜𝑜 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑ℎ𝑠𝑠 𝑖𝑖𝑖𝑖 𝑎𝑎 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦) × 100,000 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏ℎ𝑠𝑠 𝑖𝑖𝑖𝑖 𝑡𝑡ℎ𝑒𝑒 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦

Page | 14


MPH 1st Year

vii. Life Expectancy at Birth - Life expectancy at birth is defined as the average number of years a new born baby will survive if s/he is subjected to the current mortality pattern. - Life expectancy like the TFR is also a synthetic cohort measure. - It is a hypothetical measure because it is based on current death rates and actual deaths changes (usually improves) over the course of person’s lifetime. - This measure of mortality is free from distortions of age composition and thus international comparisons can readily be made. - To calculate life expectancy we need the age specific mortality rates, which are difficult to obtain, as it requires a survey of large sample size. Furthermore, as the coverage of birth and death registration data is poor, life expectancy in Nepal is usually estimated based on the census data, employing indirect techniques such as life table technique. Determinants of Mortality Determinants of mortality can be categorized into proximate (direct) and non-proximate (indirect) determinants. Proximate determinants could also be described as the biological and the behavioural causes of death, whereas the indirect determinants of mortality concern social, economic, political and cultural factors that influence mortality. Determinants of mortality differ for children and adults which are summarized separately as follows: Determinants of mortality in children i. Proximate determinants - Maternal fertility behaviour - Household environmental pollution- ARI, diarrhoeal diseases - Feeding practices – Reduced breast-feeding→malnutrition →repeated infections - Diseases- measles, pertusis, diphtheria, poliomyelitis, tetanus, etc - Injuries and poisoning ii. -

Non-proximate determinants Ecological factors Individual factors- e.g education level of mother Household factors – e.g. housing, sanitation facilities, water supply, etc. Institutional factors- accessibility and affordability of MCH services Cultural factors

Determinants of mortality in adults i. Apparent poor health: e,g, heart attack, stroke, cancer, cirrhosis of liver, etc. ii. Individual health behaviour: e.g. smoking, diet practices, alcohol and drug abuse, lack of physical activity. iii. Social determinants: marital status, educational level, income, degree of health conscious, profession, migration status iv. Environmental factors: Exposure to infectious or chemical or physical agents, occupational hazards, etc. v. Injuries: Incidental or accidental injuries vi. Health Service factors: use of health services, accessibility, affordability, etc.

©Prabesh Ghimire

Page | 15


MPH 1st Year

Standardization of Death Rates Standardization is a method of adjustment generally done for age differentials with an objective to remove the effect of differential mortality or differential structure of the subgroups in the two populations under comparison. The rates are then brought to a common base and thus made comparable. -

-

-

When comparing two or more populations with respect to a health outcome, it is tempting to compare crude rates of disease, i.e., the number of disease events divided by the size of the population. Comparisons of crude rates can be misleading because of confounding if the populations being compared have different distributions of other determinants of disease, such as age which has an important effect on many health outcomes. As a result, differences in age can distort other comparisons between populations, and this distortion is called confounding. To eliminate the distortion caused by different underlying age distributions in different populations, statistical techniques are used to adjust or standardize the rates among the populations to be compared. The two closely related techniques are commonly used to compute standardized rates that facilitate comparisons among population.

i. -

-

-

Direct standardization Direct standardization applies a standard age distribution (standard population) to the populations being compared in order to compute summary rates indicating how overall rates would have compared if the populations had had the same age distribution. This method is used when age-specific rates of disease are known for the populations being compared. The standard population is usually the population of the whole country if we are making comparison of rate in two districts. The physical meaning of direct standardized death rate of population is that it is a crude death rate that would result if the age specific death of the population under study would be applied to that of standard population. Direct standardized rate can be calculated as 𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷 𝑃𝑃 =

∑𝑎𝑎 (𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝑎𝑎𝑃𝑃 × 𝑃𝑃𝑎𝑎𝑆𝑆 ) 𝑃𝑃 𝑆𝑆

Where, 𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝑎𝑎𝑃𝑃 = Age specific death rate of population to be standardized 𝑃𝑃𝑎𝑎𝑆𝑆 = Population in a specific age group of a standard population 𝑃𝑃 𝑆𝑆 = Total population in a standard population

Steps in direct standardization i. Calculate the age specific death rates for each age group in population which is to be compared. ii. Create a new "Standard Population" for each age group by adding population say A and B for each age group or by taking one of the population itself as standard. iii. Calculate the expected number of deaths for each age group in the standard population by multiplying the standard population by the age specific rates for the population, which is to be compared. iv. Complete this process for each age group and for each population separately.

©Prabesh Ghimire

Page | 16


ii. -

-

MPH 1st Year

Indirect standardization Indirect standardization applies a standard set of age-specific rates of disease to the populations being compared in order to compute the number of cases of disease that would be expected in a given population, based on its size and age-distribution. In this method, we require the knowledge of age distribution and crude death rate of the population being compared and age-specific death rate of standard population. The formula for calculating ISDR can be expressed as: 𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝑃𝑃 = 𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝑃𝑃 =

𝐶𝐶𝐶𝐶𝐶𝐶𝑃𝑃 × 𝐶𝐶𝐶𝐶𝐶𝐶 𝑆𝑆 𝑆𝑆 ∑𝑎𝑎 (𝑃𝑃𝑎𝑎𝑃𝑃 × 𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝑎𝑎) 𝑃𝑃𝑃𝑃

𝐶𝐶𝐶𝐶𝐶𝐶𝑃𝑃 × 𝐶𝐶𝐶𝐶𝐶𝐶 𝑆𝑆 𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼 𝑜𝑜𝑜𝑜 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑ℎ 𝑟𝑟𝑟𝑟𝑟𝑟𝑟𝑟

Where, 𝐶𝐶𝐶𝐶𝐶𝐶 𝑃𝑃 = Crude death rate of population (P) being standardized 𝐶𝐶𝐶𝐶𝐶𝐶 𝑆𝑆 = Crude death rate of standard population (S) 𝑃𝑃𝑎𝑎𝑃𝑃 = Population of particular age group in population being standardized 𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝑎𝑎𝑆𝑆 = ASDR in standard population 𝑃𝑃𝑃𝑃 = Total population in the population being standardized

Numerical Example: 2. Compare the mortality rates of two population using direct standardized technique Age Group Population “A” Population “B” (in years) Population (000) Deaths Population (000) 0-10 20 400 40 10-35 50 500 120 35-55 90 450 160 55+ 40 800 80 Total 200 2150 400

Deaths 400 240 800 2560 4000

Solution, First, we consider one of the population as standard. Here, we assume population A as standard. Therefore, we calculate ASDR for each age group in population B. Age Group Population “A” Population “B” Population Deaths Population Deaths ASDR (000) (000) 0-10 20 400 40 400 10 10-35 50 500 120 240 2 35-55 90 450 160 800 5 55+ 40 800 80 2560 32 Total 200 2150 400 4000 𝐶𝐶𝐶𝐶𝐶𝐶 𝑓𝑓𝑓𝑓𝑓𝑓 𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐 𝐴𝐴 =

𝐶𝐶𝐶𝐶𝐶𝐶 𝑓𝑓𝑓𝑓𝑓𝑓 𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐 𝐵𝐵 =

2150

200000 4000

400000

©Prabesh Ghimire

× 1000 = 10.75/1000 × 1000 = 10/1000

Page | 17


MPH 1st Year

When comparing CDR of two places, mortality seems higher in city A. Now, we wish to compare two mortalities by age-adjusting the population of city B.

=

(10×20,000)+ (2×50,000)+ (5×90,000)+ (32×40,000)

=

2,030,000 200,000

𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷 𝐵𝐵 =

∑𝑎𝑎 (𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝑎𝑎𝐵𝐵 × 𝑃𝑃𝑎𝑎𝐴𝐴 ) 𝑃𝑃 𝐴𝐴

200,000

= 10.15

When this standardized mortality rate of city B is compared with CDR of City A, we can conclude that death rate of City A is higher than city B even after standardization. 3. Compare the mortality rates of two population using indirect standardized technique Age Group Population “A” Population “B” (in years) Population (000) Deaths Population (000) Deaths 0-10 20 400 40 400 10-35 50 500 120 240 35-55 90 450 160 800 55+ 40 800 80 2560 Total 200 2150 400 4000 Solution First, we consider one of the population as standard. Here, we assume population A as standard. Therefore, we calculate ASDR for each age group in population A. (Note: Usually in indirect standardization technique, the age-specific death rate of population being compared is unknown) Age Group (in years)

Population “A” Population (000)

Deaths

ASDR

0-10 10-35 35-55 55+ Total

20 50 90 40 200

400 500 450 800 2150

20 10 5 20

𝐶𝐶𝐶𝐶𝐶𝐶 𝑓𝑓𝑓𝑓𝑓𝑓 𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐 𝐴𝐴 =

𝐶𝐶𝐶𝐶𝐶𝐶 𝑓𝑓𝑓𝑓𝑓𝑓 𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐 𝐵𝐵 =

2150

200000 4000

400000

Population “B” Population (000) 40 120 160 80 400

Deaths 400 240 800 2560 4000

× 1000 = 10.75/1000 × 1000 = 10/1000

When comparing CDR of two places, mortality seems higher in city A. Now, we wish to compare two mortalities by age-adjusting the population of city B by indirect technique. 𝐶𝐶𝐶𝐶𝐶𝐶 𝐵𝐵 × 𝐶𝐶𝐶𝐶𝐶𝐶 𝐴𝐴 𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐵𝐵 = 𝐴𝐴 ∑𝑎𝑎 (𝑃𝑃𝑎𝑎𝐵𝐵 × 𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝑎𝑎) 𝑃𝑃𝐵𝐵

©Prabesh Ghimire

Page | 18


MPH 1st Year

First we calculate index of death rate as (40,000 × 20) + (120,000 × 10) + (160,000 × 5) + (80,000 × 20) 𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼 𝑜𝑜𝑜𝑜 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑ℎ 𝑟𝑟𝑟𝑟𝑟𝑟𝑟𝑟 = 400,000 Now,

𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼 𝑜𝑜𝑜𝑜 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑ℎ 𝑟𝑟𝑟𝑟𝑟𝑟𝑟𝑟 =

4,400,000 = 11 400,000

𝐶𝐶𝐶𝐶𝐶𝐶 𝐵𝐵 × 𝐶𝐶𝐶𝐶𝐶𝐶 𝐴𝐴 𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼 𝑜𝑜𝑜𝑜 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑ℎ 𝑟𝑟𝑟𝑟𝑟𝑟𝑟𝑟 10 × 10.75 𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐵𝐵 = = 9.77 11

𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐵𝐵 =

When this standardized mortality rate of city B is compared with CDR of City A, we can conclude that death rate of City A is higher than city B even after standardization. i.e. City B is healthier. Life Table According to Donald Bogue, the life table is a mathematical model that portrays mortality condition at a particular time among a population and provides a basis for measuring longevity. A life table is a table which shows, for a person at each age, what the probability is that they die before their next birthday. From this starting point, a number of statistics can be derived and thus also included in the table is: • the probability of surviving any particular year of age • the remaining life expectancy for people at different ages • the proportion of the original birth cohort still alive. Uses and Applications Life table is a simple tool used not only for mortality but also for other vital events like natality (fertility), reproduction, chances of survival etc. So it has diverse applications. Life table can be used to find the number of survivors out of 1000 at birth e.g. - Number of children likely to enter primary school at the age of 5 - The number of women entering fertile period, or no. of women reaching menopause at particular age - Expectation of life at birth - Survival rate after treatment or operation Other Applications - Life table can be used to study divorce pattern, labour force participation - Life table has also been used to estimate the population by age sex Types of Life Tables Basically life table can be categorized into two types according to reference year: i. Current Life Table ii. Cohort/ Generation Life Table

©Prabesh Ghimire

Page | 19


MPH 1st Year

i. -

Current Life Table It is based upon the mortality experience of a community for a short period of time such as one year. The current life table does not depict mortality experience of an actual cohort. Here we assume a hypothetical cohort that experience the ASDR observed during a particular time. Thus current life table can be viewed as a snapshot of current situation of mortality. It gives an excellent summary description of mortality in a year or short period of time.

ii. -

Cohort/ Generation Life Table The generation life table is based on the mortality rates experienced by a particular cohort such as all persons born in the year 2011 data are collected by following a cohort throughout its life. This life table would observe the mortality experience of that particular birth cohort from its beginning till the death of member of the cohort. Data over a long period of years are needed to complete a single life table and hence cohort life tables are not much practical and not commonly used.

-

Usually there are two ways of presenting current or cohort/generation life table: Complete and Abridge life table - In complete life table, information is given for every single year of age from birth until the last age. - In abridge life table, information is given only for broader age intervals such as X to X+1 years or X to X+5 years. - Simple abridge table is usually preferred than more detailed complete life table because it is less laborious to prepare and is reliable for most purposes and more convenient to use. Assumptions for construction of life table - There is no change in mortality rates over time, which means that the given schedule of risks remain constant. - The cohort is closed which means that there is no out migration or in-migration. Changes take place only due to mortality. - A hypothetical cohort or radix is usually set at 1000 or 10,000 persons to simplify the comparability of survivors in the life table. This is also useful to study two life tables for different times and place. - Life tables are generally proposed for homogenous sexes because there is difference in age-specific death rates for men and women. Structure of Life Table Life table consists of eight columns which are described as follows: i. First Column (x) - In this column, age is entered in serial order from zero to maximum. - Age-intervals may also be used. ii. -

Second Column (l x ) This column shows the number of persons living at age x in which the initial figure will be those of newborn babies who begin the first year of their life together. For example, 10,000 babies at birth, 95,531 survivors at age 1, 95,250 survivors at age 5 and so on.

iii. Third Column (d x ) - This column reveals the number of dead persons between each age x and the succeeding year of age (x+1). - Usually it is a age specific death.

©Prabesh Ghimire

Page | 20


-

MPH 1st Year

d x = l x -l x+1 or d x = l x × q x Thus number of survivors at age x+1 will be l x+1 = l x - d x

iv. Fourth Column (q x ) - This column presents the probable mortality rate between every age and succeeding age (x+1). - The mortality rate is obtained by dividing the number of dying persons (d x ) at each age by the number of people surviving at that age - q x = d x /l x v. Fifth Column (P x ) - P x indicates the probability of survival between the year x and x+1. - The relative P x can be obtained by subtracting q x from 1. - P x = 1-q x vi. Sixth Column (L x ) - This column portrays the average number of survivals between age x and x+n, vii. -

Under assumption of linearity, 𝐿𝐿𝑥𝑥 = 𝑛𝑛 ×

𝑙𝑙 𝑥𝑥 + 𝑙𝑙 𝑥𝑥+1 2

, where n is the age interval

Seventh Column (T x ) It shows the total number of surviving people at L x age who are likely to live for some more years. This can be calculated by adding the values in the preceeding column from bottom to top. T x = L x +L x+1 +L x+3 ……………. T x = T x-1 – L x-1

viii. Eighth Column (e0 X ) - This column gives the average life expectancy of the population at x years of age. -

𝑒𝑒𝑥𝑥0 =

𝑇𝑇𝑥𝑥 𝑙𝑙 𝑥𝑥

Age (x)

Living at age x (l x )

X years

lx= number that started life

Dying between ages x to x+1 (d x ) d x = l x -l x+1

Mortality Rate (q x )

Survival Rate (P x )

q x = d x /l x

P x = 1-q x

Living between ages x to x+1 (L x ) , 𝐿𝐿𝑥𝑥 = 𝑛𝑛 × 𝑙𝑙 𝑥𝑥 + 𝑙𝑙 𝑥𝑥+1 2

Living above age x (T x ) T x = T x-1 – L x-1

Expectation of life at age x (e0 X ) 𝑒𝑒𝑥𝑥0 =

𝑇𝑇𝑥𝑥 𝑙𝑙𝑥𝑥

Numerical Example 1. Fill up the blanks, which are marked with a question mark in the skeleton life table Age (x) 30 31

lx 762227 758580

dx ?

qx ?

Px ?

Lx ?

Tx 27296732 ?

e0 X ?

Solution: d x = l x -l x+1 d 30 = l 30 -l 31

©Prabesh Ghimire

Page | 21


MPH 1st Year

d 30 = 762227-758580 = 3647 q x = d x /l x q x = 3647/762227 = 0.005 p x = 1- q x p x = 1- 0.005 = 0.995 𝑙𝑙30 + 𝑙𝑙31 2 𝐿𝐿𝑥𝑥 = (762227+758580)/2 = 760404 𝐿𝐿30 =

𝑇𝑇30 𝑙𝑙30 = 27296732/ 762227 = 35.81

0 𝑒𝑒30 = 0 𝑒𝑒30

T 31 = T 30 – L 30 T 31 = 27296732- 760404 = 26536328 Hence, the table can be filled by calculate values as follows: Age (x) lx dx qx Px 30 762227 3647 0.995 0.005 31 758580

Lx 760404

Tx 27296732 26536328

e0 X 35.81

2. Fill in the blanks in the following skeleton life table which are marked with question marks Age (x) lx dx qx Px Lx Tx e0 X 20 90000 500 ? ? ? 4850000 ? 21 ? 400 ? ? ? ? ? Solution: Column 2 l 21 =I 20 -d 20 l 21 =90000-500 = 89500 l 22 =89500-400 = 89100 (will be required for calculating L 21 ) Column 4 q x = d x /l x q 20 = d 20 /l 20 = 500/90000 = 0.0056 q 21 = d 21 /l 21 = 400/89500 = 0.0045 Column 5 p x = 1- q x p 20 = 1- q 20 = 1-0.0056 = 0.9944 p 21 = 1- q 21 = 1- 0.0045 = 0.9955 Column 6 L x = (l x +l x+1 )/2 L 20 = (l 20 +l 21 )/2 = (90000+89500)/2 = 89750 L 21 = (l 21 +l 22 )/2 = (89500+89100)/2 = 89300 Column 7

©Prabesh Ghimire

Page | 22


MPH 1st Year

T x = T x-1 – L x-1 T 21 = T 20 – L 20 = 4850000-89750 = 4760250 Column 8 e0 20 = T 20 /I 20 = 4850000/90000 = 53.89 e0 21 = T 21 /I 21 = 4760250/89500 = 53.19 UNIT 2.3 MIGRATION AND ITS MEASURES Basic Terminology of Migration Migration is a demographic component that determines the size, growth, distribution and composition of population. Migration – Migration is a movement from one geographical area to another geographical area crossing the administrative boundaries for permanent or semi permanent residence. The starting place is known “place of origin” whilst the ending place is called ‘place of destination’. -

Life – time migration (The place of birth is different from place of residence). Recent – migration (The place of current residence is different from the place of previous residence)

Types of Migration On the basis of geographical boundaries - International Migration - Internal Migration • Rural to rural migration • Rural to urban migration • Urban to urban migration • Urban to rural migration On the basis of time - Temporary migration (less than 10 years) - Permanent Migration (More than 10 years) - Seasonal Migration (Less than six months) Determinants of Migration The determinants can be categorized into push and pull determinants. Pull factors are those determinants which attract migration at the destination and push factors are those which force to move the migrant from place of origin. Determinants Push Factors Pull Factors Economic and Poverty Prospects of higher wages demographic Unemployment Potential for improved standard of living Low wages Personal or professional development Lack of basic health and education Political Conflict, insecurity, violence Safety and security Poor governance Political freedom Corruption

©Prabesh Ghimire

Page | 23


Social cultural

Natural

and

Human right abuse Discrimination based on ethnicity, gender, religion, etc. Poor education opportunity Marriage Natural calamities Disasters (earthquakes, floods, etc.)

MPH 1st Year

Family reunification Ethnic homeland Freedom from discrimination

Measures of Migration Measurement of migration deals about the flow of migration. It measures the quantity of migrant who have shifted from their place of residence. There are four different measures of migration i. In-Migration Rate - The number of people received by an area at a specific time per thousand population of that specific area is known as in migration rate. - It can be mathematically expressed as 𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑖𝑖𝑖𝑖 − 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑡𝑡𝑡𝑡 𝑎𝑎𝑎𝑎 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝑖𝑖𝑖𝑖 𝑎𝑎 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 𝑜𝑜𝑜𝑜 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝐼𝐼𝐼𝐼 = × 1000 𝑀𝑀𝑀𝑀𝑀𝑀 𝑌𝑌𝑌𝑌𝑌𝑌𝑌𝑌 𝑃𝑃𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜 𝑎𝑎𝑎𝑎 𝑡𝑡ℎ𝑒𝑒 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝑜𝑜𝑜𝑜 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑 ii. -

Out-Migration Rate The number of out-migrants departing an area of origin per 1,000 populations at that area of origin in a given year. 𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑜𝑜𝑜𝑜𝑜𝑜 − 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑡𝑡𝑡𝑡 𝑓𝑓𝑓𝑓𝑓𝑓𝑓𝑓 𝑎𝑎𝑎𝑎 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝑖𝑖𝑖𝑖 𝑎𝑎 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 𝑜𝑜𝑜𝑜 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝑂𝑂𝑂𝑂 = × 1000 𝑀𝑀𝑀𝑀𝑀𝑀 𝑌𝑌𝑌𝑌𝑌𝑌𝑌𝑌 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃 𝑎𝑎𝑎𝑎 𝑡𝑡ℎ𝑒𝑒 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝑜𝑜𝑜𝑜 𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜

iii. Net-Migration Rate - The net effect of in-migration and out-migration on an area’s population is known as net-migration rate. - It is expressed as increase or decrease per 1,000 populations of that area in a given year. 𝑁𝑁𝑁𝑁. 𝑜𝑜𝑜𝑜 𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖 − 𝑁𝑁𝑁𝑁. 𝑜𝑜𝑜𝑜 𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜 𝑁𝑁𝑁𝑁𝑁𝑁 = × 1000 𝑀𝑀𝑀𝑀𝑀𝑀 𝑌𝑌𝑌𝑌𝑌𝑌𝑌𝑌 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃 𝑎𝑎𝑎𝑎 𝑡𝑡ℎa𝑡𝑡 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝑁𝑁𝑀𝑀𝑀𝑀 = 𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼 𝑟𝑟𝑟𝑟𝑟𝑟𝑟𝑟 − 𝑂𝑂𝑂𝑂𝑂𝑂 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑟𝑟𝑟𝑟𝑟𝑟𝑟𝑟

iv. Gross-Migration Rate - The total number of in-migrants and out-migrants per 1,000 population of the area in a given year/ period is known as gross migration rate. 𝑁𝑁𝑁𝑁. 𝑜𝑜𝑜𝑜 𝑖𝑖𝑖𝑖𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 + 𝑁𝑁𝑁𝑁. 𝑜𝑜𝑜𝑜 𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜 𝑁𝑁𝑁𝑁𝑁𝑁 = × 1000 𝑀𝑀𝑀𝑀𝑀𝑀 𝑌𝑌𝑌𝑌𝑌𝑌𝑌𝑌 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃 𝑎𝑎𝑎𝑎 𝑡𝑡ℎ𝑎𝑎𝑎𝑎 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝑁𝑁𝑁𝑁𝑁𝑁 = 𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼 𝑟𝑟𝑟𝑟𝑟𝑟𝑟𝑟 + 𝑂𝑂𝑂𝑂𝑂𝑂 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑟𝑟𝑟𝑟𝑟𝑟𝑟𝑟

Simple Measure to Calculate Internal Migration

©Prabesh Ghimire

Page | 24


MPH 1st Year

If we are interested to know the magnitude of in and out migrants then it becomes difficult to calculate. In this case we can estimate the internal migration by simply asking questions about the place of birth statistics. Based on this enumeration, the population can be classified into • Region of enumeration • Region of birth Let us assume there are three sub-divisions A,B, C (e.g. Terai, Hills and Mountain) in a country. Then we can lay out the information by classifying the populations according to region of birth and region of enumeration as shown below: Region of Birth A B C Total

Region of Enumeration A B N AA N AB N BA N BB N CA N CB N.A N.B

Total C N AC N BC N CC N.C

NA NB NC N

Here, Out-migrants for A (O A ) = N AB + N AC Out-migrants for B (O B ) = N BA + N BC Out-migrants for C (O C ) = N CA + N CB Also, In-migrant for A (I A ) = N BA + N CA In-migrant for B (I B ) = N AB + N CB In-migrant for C (I C ) = N AC + N BC In the classification, N AA , N BB , N CC are non-migrants for region A,B and C respectively. Finally, Net-migration can be calculated for each regions as follows: Net-Migration for A (NM A ) = I A - O A Net-Migration for B (NM B ) = I B – O B Net-Migration for C (NM C ) = I C – O C UNIT 2.4: NUPTIALITY AND ITS MEASURES Basic Terminologies of Nuptiality Nuptiality - The study of nuptiality deals with the frequency of marriage. - Marital status is an important element of population composition and is a significant factor in population dynamics as it affects fertility to a large extent, particularly in societies like Nepal where marriage is almost universal and most births take place within wedlock. Marital Status - The marital status consists of four categories i. Never Married ii. Married

©Prabesh Ghimire

Page | 25


MPH 1st Year

a. Single Married b. Multiple Married c. Re-Married iii. Widowed iv. Divorces/ separated a. Divorced b. Separated - In the 1952/54 censuses, information on marital status was obtained for the population aged 5 years and above, whereas the age limit for collecting the particulars related to marital status was 6 years in 1961 and 1971. However, the age limit was raised to 10 years and above in the subsequent four censuses. Determinants of Nuptiality i. ii. iii. iv. v. vi. vii. viii. ix. x. xi. xii.

Beauty Personality traits: Personality traits might be attributed to the facial shape (preferred large eyes, lips, height, ethnic group, skin, hair and capital) Being modest, intelligent Non-conflicting Income generating Education Age of spouses Being protective/ caring Social status, social norms Marital fidelity (loyalty) BMI (Body Mass Index) Waist to Hip Ratio – Reproductive potential

Simple Measures of Nuptiality Various Measures of Nuptiality includes i. Crude Marriage Rate ii. General Marriage Rate iii. Age-Sex Specific Marriage Rate iv. Total Marriage Rate v. Average Age at Marriage vi. Singulate Mean Age at Marriage vii. Crude Divorce Rate viii. Period Total Divorce Rate i. -

ii.

Crude Marriage Rate Number of marriages (including first and remarriage) in a specified area during the given year per 1,000 mid-year population of a particular age in the same year. This rate is calculated using the number of marriages and not the number of people getting married. 𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑖𝑖𝑖𝑖 𝑎𝑎 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 𝐶𝐶𝐶𝐶𝑢𝑢𝑢𝑢𝑢𝑢 𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀 𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅 = × 1000 𝑀𝑀𝑀𝑀𝑀𝑀 − 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝑜𝑜𝑜𝑜 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝑠𝑠𝑠𝑠𝑠𝑠 General Marriage Rate

©Prabesh Ghimire

Page | 26


MPH 1st Year

-

The rate is the refinement of crude marriage rate by restricting the population to marriageable age (i.e. 10 years and above) instead of whole population. 𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑜𝑜𝑜𝑜 𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤 (10 +) 𝑖𝑖𝑖𝑖 𝑎𝑎 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 𝐺𝐺𝐺𝐺𝐺𝐺 = × 1000 𝑀𝑀𝑀𝑀𝑀𝑀 − 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝑡𝑡𝑡𝑡 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝑜𝑜𝑜𝑜 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑎𝑎𝑎𝑎𝑎𝑎 (> 10 𝑦𝑦𝑦𝑦𝑦𝑦) iii. Age-Sex Specific Marriage Rate - This rate can be considered as more refined than above measures. - This considers marriage rate according to different age groups separately. - This rate is defined as the number of marriage according to different age groups separately for male and female. 𝑁𝑁𝑁𝑁. 𝑜𝑜𝑜𝑜 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑎𝑎𝑎𝑎 𝑎𝑎 𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐 𝑎𝑎𝑎𝑎𝑎𝑎 / 𝑎𝑎𝑎𝑎𝑎𝑎 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 𝑖𝑖𝑖𝑖 𝑎𝑎 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴 = × 1000 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃 𝑜𝑜𝑜𝑜 𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝑜𝑜𝑜𝑜 𝑡𝑡ℎ𝑒𝑒 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎/ 𝑎𝑎𝑎𝑎𝑒𝑒 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔

iv. -

Total Marriage Rate Total marriage rate indicates the total number of first marriage in a particular cohort. It is the total number of marriages in a cohort. The total marriage rate described the proportion of women (generally per 100 or 1,000 persons) groups of 15 to 49 years. It is computed by adding up the age-specific marriage rates of first marriages in the whole age period. 𝛽𝛽

𝑇𝑇𝑇𝑇𝑇𝑇 = � 𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴 × 1000 v. -

𝛼𝛼

Average Age at First Marriage This is the median age of those people who get married in a given year. The median age at first marriage is usually calculated separately for males and females because females typically marry at younger ages. Age at marriage with parental consent for both boys and girls is set at 18 years and if boys and girls want to marry on their own, then the minimum legal age at marriage for both boys and girls 20 years. However, the observed age at marriage is for male is 22.9 yrs and female is 19.5 yrs.

vi. Singulate mean age at marriage (SMAM) - Singulate mean age at marriage is an estimate of the average number of years lived as “Single or Never Married” by those who marry before the age of 50. - A high value of SMAM means postponement of marriage to a higher age. A high SMAM for females reduces lifetime fertility. - It is computed from the proportion of single persons or “Never Married” in each age group from 15-19 to 50-54 yrs. - According to census 2011, the SMAM for males is 23.8 yrs and for females is 20.6 yrs. vii. Crude divorce rate - The crude divorce rate is the annual number of divorces per 1000 population. - Divorce is a final legal dissolution of a marriage, that is, separation of husband and wife which confers on the parties the right to remarriage under civil, religious and/or other provisions according to the laws of each country. viii. Total period Divorce Rate

©Prabesh Ghimire

Page | 27


-

MPH 1st Year

The total period divorce rate indicates the number of divorces in an imaginary class of 1000 marriages in which divorce rates for each length of marriage are equal to those observed in the year in question. 𝑁𝑁𝑁𝑁. 𝑜𝑜𝑜𝑜 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑜𝑜𝑜𝑜 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑 𝑖𝑖 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑 𝑡𝑡ℎ𝑟𝑟𝑟𝑟𝑟𝑟𝑟𝑟ℎ 𝑎𝑎 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑 𝑖𝑖𝑖𝑖 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 𝑡𝑡 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 = × 1000 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛 𝑜𝑜𝑜𝑜 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑖𝑖𝑖𝑖 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 𝑡𝑡 𝑡𝑡𝑡𝑡 𝑖𝑖 𝑤𝑤ℎ𝑖𝑖𝑖𝑖ℎ 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢 𝑡𝑡𝑡𝑡𝑡𝑡𝑡𝑡 𝑡𝑡

UNIT 2.5: URBANIZATION AND ITS MEASURES Basic Terminology of Urbanization

Urbanization is defined as defined as the growth in the proportion of total population, which resides in urban places. Determinants of Urbanization Determinants Causes Demographic - Population increase - Migration Geographical - Location of mineral deposits - Port town - Boundary changes Social and economic - Industrialization - Specialization in occupation - Political factors - Educational and cultural centers - Transport and communication facilities Definition of urban area Municipality Act 1992 define urban area as locality - With 20,000 or more inhabitants - Having facility of electricity, road, drinking water, communication and other similar minimum urban facilities. According to Local Self-Governance Act 1999, municipality are classified into three categories on the basis on inhabitants, sources of revenue and other urban environment - Mahanagarpalika- population of 300,000 or more; having annual revenue of at least Rs. 400 million and having adequate urban facilities. - Upa-Mahanagarpalika- population of 100,000 or more; having an annual revenue of at least Rs. 100 million and having adequate urban facilities - Nagarpalika- minimum population of 20,000; having annual revenue of at least one million rupees and having basic urban facilities. Urbanization in Nepal - Nepal’s urbanization is observed to be low (27%). - Currently there are 4 metropolitan cities, 13 sub-metropolitan city, 246 municipality and 81 rural municipalities in Nepal. - Nepal’s urbanization is primarily characterized by • An increase in the number of municipalities • An expansion in the urban area • Rapid increase of population in recent years

©Prabesh Ghimire

Page | 28

Demography and Health •

MPH 1st Year

Consistent increase in the percentage share of urban population to the total population and rural population.

Measures of Urbanization There are three important measures of urbanization 1. Degree of urbanization 2. Tempo of urbanization 3. The concentration and dispersion of population Degree of Urbanization - The degree of urbanization refers to the extent to which an area is urbanized. - Since there are varieties of dimensions of urbanization process, a number of methods have been developed and adopted to measure it precisely. i. -

Percent distribution It measures the percentage of population in the urban area. Percent of urban population is simply obtained by dividing the population living in urban area by total population of a country.

Merits - This is a simple measure and easy to calculate - Easy to interpret Weakness - Does not give any indication of the percentage of population according to size. - Change in boundary of the locality from time to time ii. -

Ratio of urban to rural population It is the ratio of population living in urban area to that living in rural area. This measure measures another aspect of urbanization and is better measure of urbanization.

iii. -

Size of locality of residence of median inhabitant This index established the size of locality where the median inhabitant lives. Bigger the locality size of the median inhabitant, the greater is the degree of urbanization The index is obtained by using the formula 50 − 𝑃𝑃𝑃𝑃𝑖𝑖 𝑀𝑀𝑀𝑀 = 𝑄𝑄𝑖𝑖 + (𝑄𝑄𝐼𝐼+1 − 𝑄𝑄𝑖𝑖 ) 𝑃𝑃𝑃𝑃𝑖𝑖+1 − 𝑃𝑃𝑃𝑃𝑖𝑖 Where, MI = median inhabitant PP i = cumulative percent of the population for the locality size just under 50% PP i+1 = cumulative percent of the next locality size category Q i = upper limit of the locality size I, just under 50% iv. Mean city population size - It is the average of the sizes of the cities - Mean city population size is given by

©Prabesh Ghimire

Page | 29


𝑀𝑀𝑀𝑀 =

MPH 1st Year

2 ∑𝑚𝑚 𝑖𝑖=1 𝐶𝐶𝑖𝑖 𝑃𝑃

Where, C i = Population in the ith localities P is the total population of the country M is the total number of localities Numerical Example Calculate the size of locality of residence of median of median inhabitant in the given population distribution by categories of localities (Municipalities of Nepal, 2011) Size class distribution Municipalities Population Cumulative % Number Percent Size Percent Less than 20000 14 10.8 238,431 3.3 3.3 20000-29999 33 25.4 833,353 11.6 14.9 30000-39999 25 19.2 855,406 11.9 26.8 40000-49999 (Q i ) 19 14.6 850,327 11.8 38.6 (PP i ) 50000-99999 (Q i+1 ) 28 21.5 1,895,554 26.3 64.9 (PP i+1 ) 100000-199999 7 5.4 873,598 12.1 77 200000+ 4 3.1 1,652,845 23.0 100 130 100 7,199,514 100 Here, cumulative percent just above 50% is 64.9. Therefore the corresponding population class 5000099999 is the median class. So PP i = 38.6 PP i+1 = 64.9 Q i = 49999 (upper limit) Q i+1 = 99999 (upper limit) 50 − 𝑃𝑃𝑃𝑃𝑖𝑖 𝑃𝑃𝑃𝑃𝑖𝑖+1 − 𝑃𝑃𝑃𝑃𝑖𝑖 50 − 38.6 𝑀𝑀𝑀𝑀 = 49999 + (99999 − 49999) 64.9 − 38.6 𝑀𝑀𝑀𝑀 = 71,672

𝑀𝑀𝑀𝑀 = 𝑄𝑄𝑖𝑖 + (𝑄𝑄𝐼𝐼+1 − 𝑄𝑄𝑖𝑖 )

Tempo (Speed) of Urbanization - Tempo or speed of urbanization refers to the annual rate of change in the degree of urbanization. - Tempo of urbanization can be measured in two broad ways i. Annual change of percentage points ii. Annual average rates of change of the percent urban i. -

Annual change of percentage points One of the basic ways of measuring tempo of urbanization is calculation of absolute annual change in percentage points. This method of measuring tempo of urbanization is affected by the degree of urbanization already achieved at the beginning of the period. Annual change of percentage points is calculated by

©Prabesh Ghimire

Page | 30


𝑇𝑇𝑇𝑇𝐴𝐴 =

MPH 1st Year

𝑃𝑃𝑃𝑃𝑡𝑡+𝑛𝑛 − 𝑃𝑃𝑃𝑃𝑡𝑡 𝑛𝑛

Where, TU A = Tempo of urbanization as annual change in percentage points n = number of years PU t = Percent of urban population in time t PU t+n = Percent of urban population in time t+n ii. Annual average rate of change of percent urban - This gives the annual rate of change in number of people in urban areas per 100 population - This method assumes the growth of urbanization in three different ways a. Arithmetic (Linear) growth - If the percent of urban population is assumed to change arithmetically, then 𝑃𝑃𝑃𝑃𝑡𝑡 = 𝑃𝑃𝑃𝑃0 (1 + 𝑅𝑅𝑎𝑎 𝑡𝑡) Where, P t = Percent of urban population at time t P 0 = Percent of urban population at baseline (as start of time t) R a = arithmetic rate in the change of percent urban t = time period (no. of years) Therefore, the tempo of urbanization using arithmetic growth can be calculated as 𝑃𝑃𝑡𝑡 − 𝑃𝑃0 𝑅𝑅𝑎𝑎 = 𝑃𝑃0 × 𝑡𝑡 b. Geometric growth - If the percent of urban population is assumed to change geometrically 𝑃𝑃𝑡𝑡 = 𝑃𝑃0 (1 + 𝑅𝑅𝑔𝑔 )𝑡𝑡 Where, P t = Percent of urban population at time t P 0 = Percent of urban population at baseline (as start of time t) R g = geometric rate in the change of percent urban -

Therefore, tempo of urbanization using geometric growth can be calculated as 1

𝑃𝑃𝑡𝑡 𝑡𝑡 𝑅𝑅𝑔𝑔 = � � − 1 𝑃𝑃0

c. -

Exponential growth If the percent of urban population is assumed to change exponentially, 𝑃𝑃𝑡𝑡 = 𝑃𝑃0 𝑒𝑒 𝑅𝑅𝑒𝑒 ×𝑡𝑡 Where, R e = geometric rate in the change of percent urban

-

Therefore, tempo of urbanization using exponential growth can be calculated as 𝑅𝑅𝑒𝑒 =

©Prabesh Ghimire

1 𝑃𝑃𝑡𝑡 𝑙𝑙𝑙𝑙𝑙𝑙𝑒𝑒 � � 𝑃𝑃0 𝑡𝑡

Page | 31


-

MPH 1st Year

The most convenient model for calculating the tempo of urbanization is the exponential growth model.

©Prabesh Ghimire

Page | 32


MPH 1st Year

UNIT 3: POPULATION ESTIMATES AND PROJECTIONS -

Population estimation is the statistical method of determining a population of a particular country at a particular time between two censuses of post-census. Population estimation is done to help planners by providing magnified image of the consequences of current trends, to guide then for taking appropriate actions.

There are three types of population estimates i. Inter-censal estimates - Inter-censal estimates are estimates for the years between any consecutive censuses, based on data from both the censuses. ii. -

Post-censal estimates Post-censal estimates are estimates for years following a census, which may also use other sources. Thus an estimate of the population of Nepal for the year 2014, based on the data of last census of 2011 and the records of births, deaths and migration, from 2011 to 2014 is essentially a post-censal estimate.

iii. Future estimates and projections - Future estimates and projections are in general less accurate than the post censal estimates. - They are always based on some assumptions of the trends of population growth Assumptions for population estimation - Same growth rate continues for the projection period. - The socio-economic setting affecting the population size is fairly unchanging. - No allowance is made for the irregular fluctuations in population growth. Methods of Estimation i. Demographic Method (Natural Increase) ii. Mathematical Methods a. Linear Growth Model b. Geometric Growth Model c. Exponential Growth Model iii. Component Method i. -

ii. -

Demographic Method (Natural Increase/ Balancing Equation) In this method, the components of population growth (viz:fertility, mortality and migration) information are used. The estimate of population at time t is given by 𝑃𝑃𝑡𝑡 = 𝑃𝑃0 + (𝐵𝐵 − 𝐷𝐷 + 𝐼𝐼 − 𝐸𝐸)

Mathematical Methods In general mathematical methods are used for both inter-censal and post-censal estimates of population. It is useful for estimation of future population for shorter time period (less than 10 years).

©Prabesh Ghimire

Page | 33


MPH 1st Year

a. Linear (Arithmetic) Growth Model - Based on the assumption that the annual change in population remains the same (or population increases in arithmetic progression), the estimate of population for any time t is given by, 𝑃𝑃𝑡𝑡 = 𝑃𝑃0 (1 + 𝑟𝑟𝑟𝑟) 𝑟𝑟 =

Where, P t = Population estimate at time t P 0 = Population of base census r = Rate of population growth t = Time period

𝑃𝑃𝑡𝑡 − 𝑃𝑃0 𝑃𝑃0 × 𝑡𝑡

Alternative formula, 𝑃𝑃𝑡𝑡 = 𝑃𝑃0 + 𝑟𝑟𝑟𝑟 Where, P 0 = Population of last census

𝑟𝑟 =

𝑃𝑃𝑡𝑡 − 𝑃𝑃0 𝑡𝑡

b. Geometric Growth Model - Based on the assumption that the annual change in population increase in geometric progression, the estimate of population for any time t is given by, 𝑃𝑃𝑡𝑡 = 𝑃𝑃0 (1 + 𝑟𝑟)𝑡𝑡 1

c. -

𝑃𝑃𝑡𝑡 𝑡𝑡 𝑟𝑟 = � � − 1 𝑃𝑃0

Exponential Growth Model On the assumption that the population is continuously growing in an exponential pattern, the estimate of population for nay given time t is given by, 𝑃𝑃𝑡𝑡 = 𝑃𝑃0 𝑒𝑒 𝑟𝑟×𝑡𝑡 𝑟𝑟 =

1 𝑃𝑃𝑡𝑡 𝑙𝑙𝑙𝑙𝑙𝑙𝑒𝑒 � � 𝑡𝑡 𝑃𝑃0

Numerical Example # The population of Nepal in 1991 is 1,84,91,097 and 2001 is 2,31,51,423. Estimate the population of Nepal in 2007 and 2011 by Arithmetic, Geometric and Exponential growth method Solution: Arithmetic Growth Method First, to estimate the population, we find arithmetic rate of progression, 𝑃𝑃2001 − 𝑃𝑃1991 𝑟𝑟 = 𝑃𝑃1991 × 𝑡𝑡

©Prabesh Ghimire

Page | 34


𝑟𝑟 =

MPH 1st Year

23151423 − 18491097 18491097 × 10

𝑟𝑟 = 0.0252

Estimation of Population for 2007 We have, time (t) = 2007-1991 = 16 yrs (1991 is the base census, not 2001) 𝑃𝑃2007 = 𝑃𝑃1991 (1 + 𝑟𝑟𝑟𝑟)

𝑃𝑃2007 = 18491097 (1 + 0.0252 × 16) 𝑃𝑃2007 = 25946707

Estimation of population for 2011 Time (t) = 2011-1911 = 20 yrs 𝑃𝑃2011 = 𝑃𝑃1991 (1 + 𝑟𝑟𝑟𝑟)

𝑃𝑃2011 = 18491097 (1 + 0.0252 × 20) 𝑃𝑃2007 = 27810610

Geometric Growth Method The rate of geometric progression can be calculated as, 1

𝑃𝑃𝑡𝑡 𝑡𝑡 𝑟𝑟 = � � − 1 𝑃𝑃0

1

23151423 10 𝑟𝑟 = � � −1 18491097 𝑟𝑟 = 0.0227

Estimation of population for 2007 Time (t) = 2007-2001 = 6 yrs 𝑃𝑃𝑡𝑡 = 𝑃𝑃0 (1 + 𝑟𝑟)𝑡𝑡 𝑃𝑃2007 = 𝑃𝑃2001 (1 + 0.0227)6 𝑃𝑃2007 = 23151423(1 + 0.0227)6 𝑃𝑃2007 = 26489858 Estimate of population for 2011 Time (t) = 2011-2001 = 10 yrs 𝑃𝑃𝑡𝑡 = 𝑃𝑃0 (1 + 𝑟𝑟)𝑡𝑡

©Prabesh Ghimire

Page | 35


MPH 1st Year

𝑃𝑃2011 = 𝑃𝑃2001 (1 + 0.0227)10

𝑃𝑃2011 = 23151423(1 + 0.0227)10 𝑃𝑃2011 = 28976321 Exponential Growth Method The rate of geometric progression can be calculated as follows: 𝑟𝑟 = 𝑟𝑟 =

1 𝑃𝑃𝑡𝑡 𝑙𝑙𝑙𝑙𝑙𝑙𝑒𝑒 � � 𝑃𝑃0 𝑡𝑡

1 23151423 𝑙𝑙𝑙𝑙𝑙𝑙𝑒𝑒 � � 10 18491097

𝑟𝑟 = 0.0225

Estimation of population for 2007 Time (t) = 2007-2001 = 6 yrs 𝑃𝑃2007 = 𝑃𝑃2001 𝑒𝑒 𝑟𝑟×6 𝑃𝑃2007 = 23151423 𝑒𝑒 0.0225×6 𝑃𝑃2007 = 26496804

Estimation of population for 2011 Time (t) = 2007-2001 = 6 yrs 𝑃𝑃2011 = 𝑃𝑃2001 𝑒𝑒 𝑟𝑟×10

𝑃𝑃2007 = 23151423 𝑒𝑒 0.0225×10 𝑃𝑃2007 = 28992527

Tips for calculation in examination: - Use rounding on four places decimal. - For log e use ‘ln’ symbol in calculator

Other Concepts of Population Growth Natural Increase: Surplus of births over deaths i.e natural increase = Birth –Death Rate of Natural Increase (NIR) 𝑁𝑁𝑁𝑁𝑁𝑁 =

𝐵𝐵𝐵𝐵𝐵𝐵𝐵𝐵ℎ𝑠𝑠 − 𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷ℎ𝑠𝑠 × 100 𝑀𝑀𝑀𝑀𝑀𝑀 − 𝑌𝑌𝑌𝑌𝑌𝑌𝑌𝑌 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃 𝑁𝑁𝑁𝑁𝑁𝑁 =

©Prabesh Ghimire

𝐶𝐶𝐶𝐶𝐶𝐶 − 𝐶𝐶𝐶𝐶𝐶𝐶 10

Page | 36


MPH 1st Year

Population Growth Rate (PGR) 𝑃𝑃𝑃𝑃𝑃𝑃 =

𝐵𝐵 − 𝐷𝐷 + 𝐼𝐼 − 𝐸𝐸 × 100 𝑀𝑀𝑀𝑀𝑀𝑀 − 𝑌𝑌𝑌𝑌𝑌𝑌𝑌𝑌 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃

𝑃𝑃𝑃𝑃𝑃𝑃 = 𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅 𝑜𝑜𝑜𝑜 𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼 ± 𝑁𝑁𝑁𝑁𝑁𝑁 − 𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀 𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅

Decadal Population Growth Rate (DPGR)

𝑃𝑃2 − 𝑃𝑃1 × 100 𝑃𝑃1 Where, P 2 and P 1 are population of last census and previous census. 𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷 =

Annual Population Growth Rate (APGR) 1 𝑃𝑃2 − 𝑃𝑃1 × × 100 𝑃𝑃1 𝑡𝑡 Where, t is the time period between two censuses. 𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷 =

Population Doubling Time - Population growth expressed as a percentage is not always appropriate in order to see whether the growth of the population is fast or slow in order to see whether the growth of the population is fast or slow. (i.e to see its speed). - The quick way of estimating doubling time to divide 70 by the present annual growth rate 70 𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 = 𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃 𝐺𝐺𝐺𝐺𝐺𝐺𝐺𝐺𝐺𝐺ℎ 𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅 (%) - Doubling time is a crude way of estimating future population size, because it is calculated in the assumption that growth rate will be constant over the decade. - Calculating doubling time just explains how fast a population is growing at a present time.

©Prabesh Ghimire

Page | 37


MPH 1st Year

UNIT 4: POPULATION THEORIES AND POLICY UNIT 4.1: POPULATION THEORIES Early Thinking on Population Issues i. -

Confucius and Other Chinese Thought Confucius was a Chinese philosopher Confucius and other Chinese thinkers related population with agriculture. Doctrines of Confusiuson marriage, family and procreation were generally in the favor of population growth.

ii. -

Greek and Roman Thought In the Greek scheme of life, the individual part of the state. The purpose of marriage was procreation. Wars required a continuous demand of soldiers. Therefore, procreation was encouraged and even rewarded by Greeks and the Romans. The Spartans and the Athenians encouraged population due to expansionist policy. They also tried to avoid overpopulation and encouraged abortions and even infanticides.

-

a. Plato - According to Plato, city states should have 5040 citizens so that highest good may be achieved. - In this ideal population Plato did not include women, children and slaves. Including them the total population of an ideal city state in Plato’s time was about 50,000. - He also recommended infanticide on the grounds of eugenics. - In order to control population and maintain its highest quality, Plato recommended selective breeding among human beings. - He recommended that the age of marriage for the girls should be between 16 and 20. b. Aristotle - Aristotle maintained that fast population growth leads to increase in poverty and suggested abortions and infanticides, in order to control the size of the city state. - He also proposed family planning to be prescribed by the state. iii. a. -

Religious Thoughts Hindu Hindus have prescribed marriage as almost compulsory. According to Dharmasastras, no one can go to heaven without procreating a son. The hindu marriage aimed at the three fold ideal: fulfillment of Dharma, procreation and sex enjoyment.

b. Judaism - The sacred books of Jews emphasize the need of procreation. - Childlessness is considered as a serious misfortune. c. -

Christianity Marriage and reproduction were sometimes regarded as necessary evils. In later years, this underwent a change and marriage was said to be desirable and reproduction divinely approved mode of living.

d. Islam - The most populationistic religion is the Islam. - It is both because it prescribes polygamy and also encourages procreation.

©Prabesh Ghimire

Page | 38


iv. -

-

MPH 1st Year

Pre-Malthusian Thoughts Pre-Malthusian theory encouraged industrialization rather than agriculture. As the demand of labour increased, population size also increased, A large size population was considered an essential factor for economic and political power of the country. At that time birth rate was increased by adopting following measures: • Encouraging marriage directly • Encouraging fertility • Encouraging immigration and preventing emigration • Making punishment for illegitimate birth. Niccolo Machiavelli and Giovanni Botero were considered as precursors of Malthus. Niccolo gave the relationship between the population growth and development. Giovanni said that population after increasing for some time cannot continue to increase at the same rate; it may grow slowly or even may start declining.

Malthusian Theory of Population: The most important theory in the history of demography was presented by Thomas Robert Malthus. In his theory Malthus laid down two postulates: • First, that food is necessary to the existence of man • Secondly, the passion between the sexes is necessary and will remain in its present state The following propositions were put forth by Malthus to establish his theory: i. Population is necessarily limited by means of subsistence ii. Population invariably increases when the means of subsistence increases unless prevented by some very powerful and obvious checks. iii. These checks, and the checks which repress the superior power of population and its effects on a level with means of subsistence, are all resolvable into moral restraint, vice and misery.

Therefore, Malthus concluded that food supply is subject to the law of diminishing returns and grows in arithmetic progression (1,2,3,4,5,6,…) while the population left to itself grows in geometric progression (1,2,4,8,16,32,….). Since the population increases at a faster rate than the food supply, there is bound to be disequilibrium between the two and this disequilibrium has tendency to widen as time passes. The disequilibrium would result in starvation, misery and death. It can be prevented by taking preventive checks or vice like late marriage, abstinence, etc. If however, society does not control the growth of population, nature will come into operation and undertake positive checks like diseases, earthquakes, famines, floods, natural disasters, etc. In the long-run, nature will maintain a balance between means of subsistence and size of population.

©Prabesh Ghimire

Page | 39


MPH 1st Year

Significance of the theory: i. Inspite of limitations, the theory played important role because it emphasized the need for increasing food production and controlling the growth of population. ii. This theory alerted the government and people of the world about the dangers of unrestrained growth of population. Criticisms: i. The ratio of arithmetic progression of means of subsistence and the geometrical progression of population growth were never proved. ii. Malthus did not clearly distinguish between fecundity and fertility or the physiological capacity to reproduce and the actual reproductive performance. iii. The classification of checks on population growth as preventive and positive were cited as an example of poor classification, since they were not independent categories. iv. Malthus placed undue emphasis on the limitation of the supply of land. Agricultural production tremendously increased through agricultural revolution in the 19th century. v. Malthus underestimated the importance of industrial development in increasing the means of subsistence. vi. He favoured postponement of marriage and even total abstinence. vii. Malthus could not foresee that in future, family planning techniques may be devised to control growth rate of population. NEO-MALTHUSIANISM -

Neo-Malthusians are the successors of Malthus. They were keen supporters of family planning movement. According to them, Malthus was the first thinker who established that uncontrolled birth control must be popularized. Among the most important neo-Malthusian thinkers may be mentioned Mary Stopes of Great Britain and Margaret Sanger of USA. These people popularized chemical and mechanical methods of birth control.

The Neo-Malthusians maintain that in the second edition of his essay, Malthus concluded that population cannot be expected to be controlled by moral restraint alone. Moral restraint is a means which cannot be expected to be practiced by ordinary people. Therefore, Malthus was prepared to allow artificial means of birth control. Neo-Malthusians have advanced the following arguments in favor of their artificial birth control movement. i. Birth control is necessary to limit the family size in the context of available economic means, otherwise the standard of living will fall down considerably. ii. Birth control is equally necessary to limit the burden on world economy. This has already reached its saturation point. Therefore, it has no more capacity to feed the additional growing number of population. iii. Birth control is necessary on the ground of health and medical care as well. iv. Those-who oppose the neo-Malthusian approach maintained that birth control is unnatural. NeoMalthusians point out that if birth control is unnatural, the same can be said about wearing clothes since man is born nude and this is his natural condition. Despite of criticism and opposition to this theory, message gradually spread in the west and also in the east.

©Prabesh Ghimire

Page | 40


MPH 1st Year

Demographic Transition Theory -

i. -

Demographic transition means the progress of country from one demographic condition to a different stage. Several demographers such as Landry in 1909 and Warren Thompson in 1929 attempted to construct a typology to describe the demographic transition from condition of high mortality and high fertility to the condition of low mortality and low fertility. None of these demographers however made an attempt to explain these changes. In 1947, C.P. Blacker identified five phases of the demographic transition as follows: High Stationary Stage The high stationary stage is characterized by high birth rates and death rates giving a small population growth. High birth rate were because of • No birth control/ family planning • High infant mortality rate • Children needed to work • Religious beliefs encouraging large families

-

High death rate were because of • Disease and plague • Famine, uncertain food supply, poor diet • Poor sanitation

ii. -

Early Expanding Stage The early expanding stage characterized by high birth rates and high but declining mortality rates resulting high population explosion. Fall in death rate are observed due to • Improved medical care (vaccination, hospitals, new drugs) • Improved sanitation and water supply • Improvements in food production • A decrease in child mortality

-

iii. Late Expanding Stage - The late expanding stage is characterized by death rates declining much faster than birth rates resulting in population explosion. - Fall in birth rate is because: • Family planning- contraceptives, sterilization • Lower infant mortality rate • Increased industrialization and mechanization • Equal status of men and women, allowing them to follow own careers. iv. Low Stationary Stage - The low stationary stage is characterized by both birth rates and death rates resulting in fluctuating or slightly a slow population.

©Prabesh Ghimire

Page | 41


v. -

MPH 1st Year

Declining stage The declining stage is characterized by death exceeding birth (death rate declining much faster than birth rates) resulting in negative growth rate. Several developed countries appear to be entering fifth stage. If this trend continues, country will eventually observe a decrease in total population.

Criticism of Demographic Transition Theory i. This theory was based on the experience of population changes in western countries. But since the population growth in different countries does not follow identical patterns, this theory is only a broad generalization. ii. This theory fails to explain the phenomenon of the “baby boom” in western countries after the Second World War. iii. This theory does not provide a theoretical explanation of fertility as a force in demographic transition. iv. This theory cannot be called a theory in real sense. Demographic Transition of Nepal - In Nepal, both fertility and mortality appear to start declining from 1970. - During 1995 to 2010, birth rates declined from 30 to 24 per thousand populations. - The population of Nepal is still growing faster. - In terms of demographic transition, it is in its third stage.

©Prabesh Ghimire

Page | 42


MPH 1st Year

UNIT 4.2: POPULATION POLICY Concept of Population Policy -

Population policy represents a strategy for achieving a particular pattern of population change. Population policies are the policies established by government to control population growth. Population policy includes deliberate effort by a national government to • Retard growth • Promote growth • Maintain growth

Type of population policies According to Paul Meadows, any of the following four types of population policies are adopted by less developed country i. ii.

First Type: Policy to reduce the rates of population growth where government provides infrastructure; Second Type: Policy to reduce the population growth but entirely on voluntary basis and the government simply educates the person about the need for such approach. iii. Third Type: Policy to reduce birthrates and have small families and family who have crossed the permitted threshold are sterilized iv. Fourth Type: Instituting packages of disincentives if there is need for conception control and packages of incentives, if there is need for higher rates of replacements (as in France and singapore)

Population Policy of Nepal Chronological Development of Population Policy in Nepal - Population issues have been an integral part of development planning in Nepal since the first plan (1956-61). - The importance of population policy has been explicitly mentioned in development planning since the third plan, 1965-70. Plan Period Development of Population Policy First and - Both plan focused on resettlement policy Second Plan - There were programs to redistribute population from the densely populated hill region to sparsely populated terai region - FPAN was established at private level in 1959 Third Plan - This plan period focused on family planning programmes Period - Official family planning programme was established in 1968 Fourth Plan - Vital registration system was introduced in some districts as a pilot project Period to - In sixth plan, due attention was given to manage population distribution and Seventh internal migration. Plan Period - In 1983, National Population Strategy was developed - In seventh plan, the population policy document was more comprehensive in dealing with different issues such as women and development, child development, family planning and concept of unmet need, population and development and other issues. Eighth Plan - Population strategy was revised to address consequences of high population Period growth rate. - Objective of the plan was to bring balance between population growth and socioeconomic development and the environment.

©Prabesh Ghimire

Page | 43


Ninth Plan Period Tenth Plan Period Eleventh Plan (20072010) Twelfth Plan (2010-13) Thirteenth Plan (201315) -

MPH 1st Year

This plan addressed the need of the Population Perspective Plan to manage population and reduce poverty. Long term objective of reducing the TFR to replacement level within 20 years was adopted. This was called the poverty reduction strategy paper The major objectives of population management was to integrate population into development activities and manage the migration process The Objectives were to support poverty alleviation by reducing the population growth rate, integrating population management process with development programmes and promote SRH rights. One of the emphasized program was to prepare Population Perspective Plan Objectives were to promote small families, reduce population growth, launch special program for youths, increase access to SRH, etc. Thirteenth plan has a long-term perspective of transforming Nepal into a developing country from least developed country within next ten years. National Population Policy was launched in 2015

National Population Policy The National Population Policy was endorsed in 2015 (2071 BS). This overarching policy contains nine areas of focus and 78 strategies. Objectives of National Population Policy - To establish coordination between population and socio-economic development for overall development of the society. - To ensure people’s reproductive health and reproductive rights as fundamental human rights. - To promote gender equality and social inclusion in all sustainable development strategies. - To plan external, internal migration and urbanization in a systematic way. Targets SN Indicators 1 TFR, per female 2 Annual growth rate, percentage 3 CDR, per 1000 4 IMR, per 1000 live births 5 Average life expectancy 6 Average family size 7 Absent population, percentage 8 Literate percentage (>10 yr age) 9 Urban population, percentage

Targets for 2034 2.1 1.1 5 25 75 4.1 5 95 60

Major Policies of National Population Policy are - Coordination of population and development work to integrate population management in all development programs by all concerned partners. - Develop reproductive health, family planning and safe abortion as right based program. - Creating an appropriate environment for a healthy lifestyle. - Regulating internal and external migration for planned urbanization.

©Prabesh Ghimire

Page | 44


-

-

MPH 1st Year

Promoting policies, laws, institutional arrangements to mainstream targeted groups (minority, marginalized, social and economically deprived population, persons with physical and mental disabilities, etc.) in all population and development programs. Strengthening the organizational structures to develop policies, plans and ensure proper implementation, monitoring and evaluation of population and development programs. Undertaking Information, education and communication strategy (IEC) to support such program Implementation of development programs only after studying the impact on population. Creating employment opportunities for the younger active population and capitalizing on the Demographic Dividend.

Population Perspective Plan (2010-2031) A long-term population perspective plan (2010-31) was adopted by Government of Nepal in 2010. Key themes - Poverty reduction - Gender mainstreaming - Social inclusion The general objective of the PPP is to enhance the quality of the lives of Nepal’s population. The specific objectives suggested are: • Integration of population concerns in all areas of development and environment. • Facilitation of rapid demographic transition. • Facilitation of spatio-economic development processes conducive to poverty alleviation, sustainable urbanization and migration. • Institutional arrangements and implementation mechanisms for the coordination, implementation and monitoring of population programmes. The need for the PPP was conceived on three main grounds: • Integration of population concern at the policy level so that the PPP becomes the comprehensive document that compliments other sectoral plans. • To help prioritize specific sectoral policy/programme areas related to population that impact on poverty alleviation and sustainable development. • To attempt to address commitments that Nepal made in endorsing plans of action related to issues of population in various international forums, particularly ICPD (1994) and MDGs 2000-2015. Core areas of PPP i. Demographic Analysis - Under this area, the trend and differentials in demographic indicators of Nepal according to 25 years projection at five year intervals are analysed. ii. -

Reproductive Health (RH) Reproductive health is one of the main focus areas of the ICPD. Accordingly, the plan in the RH area attempts to develop reproductive health as rights within the socio-cultural context of the country.

iii. Economic Dimension - This includes the integration of population and development and shows the impact of economic policies on access to social services. - Also discussed is the implication of economic activities on population processes, with a special emphasis on the poor and disadvantaged populations.

©Prabesh Ghimire

Page | 45


MPH 1st Year

iv. Poverty Dimension - This reviews the poverty situation of Nepal and attempts to establish the link between population and poverty. v. -

Spatial Dimension This section emphasizes the issue of urbanization and migration in Nepal.

vi. Gender Mainstreaming - This discusses the legal, institutional and socio-economic aspects of women and discusses measures for interventions against discrimination. vii. Social Dimension - This section focuses on the social and cultural aspects of Janajati and Dalit in detail. viii. Decentralisation - This focuses on local level population management and includes the importance of decentralising population management and data collection at the local level. ix. Institutional Mechanism - Institutional mechanism is suggested particularly to monitor and evaluate the implemented population and development programmes. UNIT 5: HUMAN DEVELOPMENT INDEX Concept of Human Development Index The Human Development Index (HDI) is a summary composite index that measures a country's average achievements in three basic aspects of human development: health, knowledge, and income. The HDI sets a minimum and a maximum for each dimension, called goalposts, and then shows where each country stands in relation to these goalposts, expressed as a value between 0 and 1. Components of HDI

©Prabesh Ghimire

Page | 46


MPH 1st Year

Construction technique of HDI In order to calculate HDI, following data for different dimensions/ indicators are required: i. Life expectancy at birth ii. Mean Years of Schooling iii. Expected Years of Schooling iv. Per Capita Income Steps of Construction: Step 1. Creating the dimension indices - Minimum and maximum values (goalposts) need to be set in order to transform the indicators into indices between 0 and 1. - The minimum and maximum values have been set as given in the table: Dimension Dimension/Indicator Minimum Value Maximum Value Health Life Expectancy at Birth 20 85 Education Mean Years of Schooling 0 20 Expected Years of Schooling 0 18 Standard of Living GNI Per Capita PPP USD 100 75,000 -

-

-

In the next step, dimensional index are calculated by using the following formula Dimension index =

actual value − mimimum value maximum value − minimum value

Now combined education index is calculated using the following formula If MSI = Mean years of schooling index ESI = Expected years of schooling index Then, (MSI + ESI) Combined Education Index = 2 For income index log is taken as

Income index =

ln⁡ (actual value) − ln⁡ (mimimum value) ln⁡ (maximum value) − ln⁡ (minimum value)

Step 2: Aggregating the dimensional indices - Finally HDI is calculated by aggregating all three dimension indices. - HDI is the geometric mean of the three dimension indices. 𝐻𝐻𝐻𝐻𝐻𝐻 = 3�𝐼𝐼𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙 × 𝐼𝐼𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒 × 𝐼𝐼𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖

Where, 𝐼𝐼𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙 = Life Expectancy Index 𝐼𝐼𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒 = Combined Education Index 𝐼𝐼𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖 = Income Index

©Prabesh Ghimire

Page | 47


MPH 1st Year

Current position of countries in HDI According to Human Development Report 2015, Norway (0.944), Australia (0.935) and Switzerland (0.930) are the top three countries in terms of HDI rankings of 2014. Niger has the lowest HDI ranks 188th position with HDI index (0.348). Nepal stands in the 145th ranking with HDI index of 0.548. Nepal has been categorized among the countries with low human development. For Nepal, Life Expectancy at Birth = 69.6 Expected years of schooling = 12.4 Mean years of schooling = 3.3 Gross National Income (GNI) per capita = 2311 In SAARC region, HDI Rank in SAARC 1 2 3 4 5 6 7 8

Country Sri Lanka Maldives India Bhutan Bangladesh Nepal Pakistan Afghanistan

HDI Rank in World 73 104 130 132 142 145 147 171

HDI Index

Category

0.757 0.706 0.609 0.605 0.570 0.548 0.538 0.465

High Human Development Medium Human Development

Low Human Development

UNIT 6: POPULATION, ECOLOGY AND DEVELOPMENT Population Explosion and Its Effect in Ecology and Public Health Impacts of population growth on ecology i. Impacts on water resources - As global population increases, so does the demand for water. - Today, more than 2 billion people live in 47 countries that are experiencing water stress or scarcity. By 2025, based on projections of population growth, even more people (more than 3.1 billion) may live under water-scarce or water-stressed conditions. - In most of the countries where water shortage is severe and worsening, high rates of population growth exacerbate the declining availability of renewable fresh water. ii. -

Impact on croplands Global food production depends on two critical inputs: cropland and water availability. These two inputs are currently under pressure from increasing human population. FAO estimates that 37 countries face a crisis over food. Prices of cereals are up 129% since 2006.

©Prabesh Ghimire

Page | 48


MPH 1st Year

iii. Impact on forest ecosystem - The future availability of forest resources for food, fuel and shelter looks discouraging in those countries experiencing high deforestation rates. - Based on current deforestation trends, the number of people living in forest-scarce countries may increase to 3.1 billion by 2025 and to 4.1 by 2050. iv. Impact on energy resources - The International Energy Outlook 2016 projects the levels of energy demand will rise over the next three decades (2012-2040). - Much of the world increase in energy demand occurs among the developing non-OECD nations, where strong economic growth and expanding populations lead the increase in world energy use. Impacts of Population Growth on Public Health i. Impacts on Water - Water supply shortage - Pollution of water sources and distribution of poor quality drinking water ii. -

Impacts on health services Increased demand for services (e.g. immunization, maternal health services) Expansion of public health services (increase logistics supply, drugs, equipments and vaccines) to meet the needs of growing population. Increased investments in health care and disease prevention.

iii. Impacts on food supply - Rapid population growths in many poor countries have lead to chronic food shortages. - Chronic food shortages and crisis may exacerbate problems of undernutrition. iv. -

Impacts on environment Over-crowding and poor housing Increased pollution of air, land and water impacting population health Loss of biodiversity

Interrelationship between population resources, environment and sustainable development - Population and deforestation and agriculture development - Population and employment including labour force - Population growth and education - Population, food and nutrition - Population and water resources - Population and urbanization

©Prabesh Ghimire

Page | 49


MPH 1st Year

IMPORTANT FORMULA Fertility

Crude Birth Rate General Fertility Rate Age Specific Fertility Rate Total Fertility Rate

Gross Reproduction Rate Net Reproduction Rate Mortality

Crude Death Rate

Age Specific Death Rate Infant Mortality Rate Neonatal Mortality Rate Maternal Mortality Ratio Direct Standardized Death Rate Indirect Standardized Death Rate

Population Projection Balancing Equation (Demographic Method) Arithmetic Growth

©Prabesh Ghimire

𝐶𝐶𝐶𝐶𝐶𝐶 =

𝐺𝐺𝐺𝐺𝐺𝐺 =

𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏ℎ𝑠𝑠 × 1000 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 𝑀𝑀𝑀𝑀𝑀𝑀 − 𝑌𝑌𝑌𝑌𝑌𝑌𝑌𝑌 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃

𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏ℎ𝑠𝑠/ 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 × 1000 𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 15 − 49

𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏ℎ𝑠𝑠 𝑡𝑡𝑡𝑡 𝑚𝑚𝑚𝑚𝑚𝑚ℎ𝑒𝑒𝑒𝑒 𝑜𝑜𝑜𝑜 𝑎𝑎 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴 = × 1000 𝑚𝑚𝑚𝑚𝑚𝑚 − 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 𝑓𝑓𝑓𝑓𝑓𝑓𝑓𝑓𝑓𝑓𝑓𝑓 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝑖𝑖𝑖𝑖 𝑡𝑡ℎ𝑒𝑒 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 𝑇𝑇𝑇𝑇𝑇𝑇 =

∑7𝑖𝑖=0 ASFR ∗ age interval 1000

GRR = TFR * proportion of female births 𝑇𝑇𝑇𝑇𝑇𝑇 =

7

5 �𝑖𝑖=0(ASFR × S) 1000

𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑ℎℎ𝑠𝑠 × 1000 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 𝑀𝑀𝑀𝑀𝑀𝑀 − 𝑌𝑌𝑌𝑌𝑌𝑌𝑌𝑌 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃 𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑜𝑜𝑜𝑜 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑ℎ𝑠𝑠 𝑖𝑖𝑖𝑖 𝑎𝑎 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 𝑖𝑖𝑖𝑖 𝑡𝑡ℎ𝑒𝑒 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴 = × 1000 𝑚𝑚𝑚𝑚𝑚𝑚 − 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝𝑝 𝑖𝑖𝑖𝑖 𝑡𝑡ℎ𝑒𝑒 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑎𝑎𝑎𝑎𝑎𝑎 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 𝐶𝐶𝐶𝐶𝐶𝐶 =

𝐼𝐼𝐼𝐼𝐼𝐼 =

𝑁𝑁𝑁𝑁𝑁𝑁 = 𝑀𝑀𝑀𝑀𝑅𝑅 =

(𝑁𝑁𝑁𝑁. 𝑜𝑜𝑜𝑜 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑ℎ𝑠𝑠 𝑜𝑜𝑜𝑜 𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖 𝑖𝑖𝑖𝑖 𝑎𝑎 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦) × 1000 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏ℎ𝑠𝑠 𝑖𝑖𝑖𝑖 𝑡𝑡ℎ𝑒𝑒 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦

(𝑁𝑁𝑁𝑁. 𝑜𝑜𝑜𝑜 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑ℎ𝑠𝑠 𝑜𝑜𝑜𝑜 𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛𝑛 (0 − 28 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑) × 1000 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏ℎ𝑠𝑠 𝑖𝑖𝑖𝑖 𝑡𝑡ℎ𝑒𝑒 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦

(𝑁𝑁𝑁𝑁. 𝑜𝑜𝑜𝑜 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑ℎ𝑠𝑠 𝑖𝑖𝑖𝑖 𝑎𝑎 𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦) × 100,000 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙 𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏ℎ𝑠𝑠 𝑖𝑖𝑖𝑖 𝑡𝑡ℎ𝑒𝑒 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷 𝑃𝑃 =

∑𝑎𝑎 (𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝑎𝑎𝑃𝑃 × 𝑃𝑃𝑎𝑎𝑆𝑆 ) 𝑃𝑃 𝑆𝑆

𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝑃𝑃 =

𝐶𝐶𝐶𝐶𝐶𝐶 𝑃𝑃 × 𝐶𝐶𝐶𝐶𝐶𝐶 𝑆𝑆 𝑆𝑆 ∑𝑎𝑎 (𝑃𝑃𝑎𝑎𝑃𝑃 × 𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝑎𝑎) 𝑃𝑃𝑃𝑃

𝑃𝑃𝑡𝑡 = 𝑃𝑃0 + (𝐵𝐵 − 𝐷𝐷 + 𝐼𝐼 − 𝐸𝐸) 𝑃𝑃𝑡𝑡 = 𝑃𝑃0 (1 + 𝑟𝑟𝑟𝑟)

Page | 50


𝑟𝑟 =

1

𝑃𝑃𝑡𝑡 𝑡𝑡 𝑟𝑟 = � � − 1 𝑃𝑃0 𝑃𝑃𝑡𝑡 = 𝑃𝑃0 𝑒𝑒 𝑟𝑟×𝑡𝑡

Exponential Growth

𝑟𝑟 =

Miscellaneous Rate of Natural Increase

Decadal Population Growth Rate

©Prabesh Ghimire

𝑃𝑃𝑡𝑡 − 𝑃𝑃0 𝑃𝑃0 × 𝑡𝑡

𝑃𝑃𝑡𝑡 = 𝑃𝑃0 (1 + 𝑟𝑟)𝑡𝑡

Geometric Growth

Population Growth Rate

MPH 1st Year

1 𝑃𝑃𝑡𝑡 𝑙𝑙𝑙𝑙𝑙𝑙𝑒𝑒 � � 𝑡𝑡 𝑃𝑃0

𝑁𝑁𝑁𝑁𝑁𝑁 −

𝑃𝑃𝑃𝑃𝑃𝑃 =

𝐶𝐶𝐶𝐶𝐶𝐶 − 𝐶𝐶𝐶𝐶𝐶𝐶 10

𝐵𝐵 − 𝐷𝐷 + 𝐼𝐼 − 𝐸𝐸 × 100 𝑀𝑀𝑀𝑀𝑀𝑀 − 𝑌𝑌𝑌𝑌𝑌𝑌𝑌𝑌 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃

𝑃𝑃𝑃𝑃𝑃𝑃 = 𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅 𝑜𝑜𝑜𝑜 𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼𝐼 ± 𝑁𝑁𝑁𝑁𝑁𝑁 − 𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀 𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅 𝐷𝐷𝐷𝐷𝐷𝐷𝐷𝐷 =

𝑃𝑃2 − 𝑃𝑃1 × 100 𝑃𝑃1

Page | 51

Demography and Health

Recommend Documents