Dialogue January-March, 2005, Volume 6 No. 3
Change in the Age Structure of India’s Population (1881-2001)
Abstract
Age structure of any region is the consequence of birth rate, death rate, migration and the expectation of life at birth. This study examines the spatial and temporal changes in the age-sex structure of India’s population by studying in detail the shift in each age-cohort from 1881 to 2001. In addition, the paper examines the variations in the pattern of age-sex structure between the two regions of India with diverse demographic profiles – the four northern states (Bihar, Madhya Pradesh, Rajasthan and Uttar Pradesh) and the four southern states (Andhra Pradesh, Karnataka, Kerala, Tamil Nadu). This study is based on the hypotheses that a slow but gradual decline in fertility and a rise in the expectation of life at birth have changed the age-sex composition of India’s population; different age-cohorts have different demographic response to the impact of fertility and mortality change in the population; and change in the age-structure is more pronounced in the demographically developed states than demographically under developed states. The data are derived largely from Census. The major inference is that the change in the India’s age structure has been rather gradual till recently. The spatial pattern of the change in the age-sex structure is also at variance. Southern states have experienced faster change in the age-sex structure of the population than the northern states. Cohort-wise, change is more visible in the 0-14 and 60+ than the productive age-group.
Introduction
Change in the age structure of any region is the consequence of its birth rate, death rate, migration and the expectation of life at birth. There can be many situations incorporating all these factors. Few of these situations are well represented by the demographic transition model of Thomson (1929) and Notestein (1945) where only the two former indicators are considered. In the first stage of the model, there is high birth rate and high death rate with a consequential low growth rate. Age-structure at this stage is in favour of the lower age group, as due to poor development of medical facilities the expectation of life at birth is very low. In this case, since there is a large young-age population and small working-age population, the dependency rate is high. But as and when the demographic transition model moves into next stages, the shape and size of the age-structure (which is well depicted by age-sex pyramid graph) tends to change in favour of the upper age groups. In this case, the burden of dependency on working age-group population declines and increase in the working age group population promotes per capita income growth, as there are more earners. When the transition completes, the old-age dependency ratio increases and the income growth deteriorates (Bloom and Williamson, 1997).
In the theory of under population, over population and optimum population, under and optimum terms have been used in the context of role of population in the overall growth of the national income. And the age-group, which contributes to the growth of the national income, is 15-59 (in some cases the upper limit is more), which is also called working age group or ‘demographic bonus’ or ‘window of opportunity’. The age group below and above 15-59 is called dependent population, which produces little but consumes the savings of the working group and lowers the overall saving rates and growth rate. The life cycle theory of James Tobin (1967) held that the national saving rate should increase with faster population growth. It says that the young cohorts (15-29) borrow, prime (30-49) and middle aged (50-64) save and amortize, while the elderly (65+) spend savings.
Literature Review
There have been number of studies showing the relationship of changing age structure and its implications on the economic growth, saving rates, demand of goods and services etc. In some of these studies, the relationship has been proved significantly. But, there are some studies in which no clear-cut relationship has been observed. In a paper by K. Navaneetham (2004) on South and South-East Asia, the author argues that since the advent of the “miracle economies” in East Asia, the role of age structure on economic growth has attracted the attention of researchers. He observes that the ‘window of opportunity’ seems to have had a positive impact on economic growth in all Southeast Asian countries except for the Philippines. It was observed that the age structural transition is not uniform among the countries of South and Southeast Asia. The differences in the age structural transition are due to differences in the nature of fertility and mortality decline among these countries. The South Asian countries benefited little from the age structural transition. His study further indicates that macro economic growth follows the life cycle theory in the case of Southeast Asian economies. In his regression analysis, he found that the share of population in the age-group 25-49 had a significant negative impact on economic growth. But the age-group 50-64 had a positive effect on the economic growth. This is because the former age-group consumes most of their earning and therefore they are unlikely to save. But in the latter age-group, people have higher rate of saving and lower rate of consumption.
Mason (1988) and Lee et. al. (1997) have also postulated that the ‘demographic gift’ has contributed significantly to the economic growth of East Asian countries. A Study by Asian Development Bank (1997) confirms that the demographic transition in East Asian countries has played a favourable role for rapid per capita income growth. Bloom and Williamson (1997) have indicated that age structure has transitional impact on the economy. They studied 78 Asian and non-Asian countries and conclude that growth of the working aged population has had a powerful positive impact on growth domestic product (GDP), while growth of the total population has had a negative impact. They further argued that growth of the dependent population (0-14 and 65+) slowed down the economic growth. However, the impact is not uniform between young and old-age population. Although the growth of population under age 15 was negatively associated with the GDP per capita growth rate, there was no significant relationship with the growth of the elderly population.
Beherman et.al. (1999) in his study of 164 countries concludes that economic outcomes clearly follow the age patterns. Lindh (1999) in his study of the OECD countries found that the age structure of the population affects aggregate saving, which affects growth through investment. He has classified the age structure in five groups as 0-14 (young), 15-24 (youth), 25-49 (prime working), 50-64 (middle) and 65+ (old age) for studying the impact on economic growth. As the young population (0-14) is dependent on the adults for their consumption, they incur health and education expenditures in the economy. The youth population (15-24) also consumes through health and education; however, the pattern of consumption behaviour is likely to be different from young-age population due to differences in the needs and services. The prime working group population (aged 25-49) uses most of the earned income to buy a house and raise their children and therefore they save little. The population in the middle aged group 50-64 is likely to earn higher income because of their experience and also to have a higher saving rate than the 25-49 age group. As the old-age people (65+) generally retire, they depend mostly on others for their consumption needs, particularly in health. His results indicate that age effects on saving do not primarily arise through a direct life cycle mechanism but that changes are cumulative, and reinforced with a delay by growth mechanisms. He found that combined baby boom effects were more likely to increase consumption than saving as taxes were lowered, thus fueling inflation.
Liddle (2000) use a simulation model that considers sustainability on several levels by calculating production, consumption, investment, population growth/change and environmental pollution less environmental quality upgrading investment. He concludes that when the Rich countries had considerably higher population growth, but similar levels of per capita final goods consumption, they ultimately consumed less pollution (both cumulatively and yearly in the later periods). Similarly, there was less pollution on a system-wide (i.e., global) level (in part because the rich countries exported less pollution). He hypothesized that societies are more likely to make such investments when their per capita GDP are higher and are more likely to invest in general when their per capita consumption is above a subsistence level and their aged and young populations are relatively smaller than their working population (aged 18-64 in his case).
The tension between the dependency rate and life-cycle models was addressed in the 1980s by Maxwell Fry and Andrew Mason (1982) and Mason (1988). These authors developed what they called a “variable rate-of-growth effect” model to link youth dependency and national saving rates. Their model rests on the premise that decline in the youth dependency rate may induce changes in the timing of life-cycle consumption. If consumption is shifted from childrearing to later, non-childrearing stages of the life cycle, aggregate savings rise with a strength that depends directly on the growth rate of national income. As a result, the model argues that the saving rate depends on the product of the youth-dependency ratio and the growth rate of national income (the “growth-tilt effect”), as well as on the dependency ratio itself (the “level effect”). Higgins and Williamson (1997) in their study argue that the sustained high fertility and falling mortality leave households and governments burdened with high youth dependency rates, and therefore unable to save more than a small share of household incomes or tax revenues. What does a child dependency burden cost? Obviously the answer depends both on the number of children (quantity) and expenditures per child (in economic jargon, their quality): households tend to substitute quality for quantity as their income rise. They further observed that about two-thirds of this burden was on parents (including the opportunity costs of mothers’ time), while one-third was on governments (most of which is on publicly financed formal education). These burdens seem big enough to worry about, even for an economy, in which children are a relatively small share of the total population.
Spraggins et. al., (2002) in their paper analyse the impact of the age and sex structure from 2000 Census data of the United States on national and sub-national levels and drew a comparison with data from the 1990 census. Their paper showed how the U.S. age- sex structure continues to shift at all levels of geography in United States. They have also shown that the median age of the United States is 35.3 years, which was highest ever. The increase in the median age reflects an aging baby boom generation. However, the 65 plus and overall population increased at slower rate than the overall population for the first time in any census. This slow growth reflects the relative low number of people reaching age 65 during the past decade because of the relative low number of births in the late 1920s and early 1930s. In 2000, the number of males edged closer to the number of females, raising the male-female ratio from 95.1 in 1990 to 96.3 in 2000.
Objectives
This study is being conducted with the following objectives:
1. to examine the spatial and temporal changes in the age structure of India’s population;
2. to identify the age-cohorts with significant temporal changes;
3. to ascertain the impact of decline in the fertility and mortality and increase in the expectation of life at birth on different segments (age-cohort groups); and
4. to compare the variations in the pattern of age-sex structure between the two regions of India with diverse demographic profiles – the four northern states of Bihar, Madhya Pradesh, Rajasthan and Uttar Pradesh (also nomenclatured as BIMARU states) and the four southern states of Andhra Pradesh, Karnataka, Kerala and Tamil Nadu.
Hypothesis
1. A slow but gradual decline in fertility (partly on account of state policy and programme effects) and a rise in the expectation of life at birth have changed the age-sex composition of India’s population.
2. Different age-cohorts have different demographic response to the impact of fertility and mortality change in the population.
3. Change in the age structure is more pronounced in the demographically developed states (southern states) than demographically under developed states (northern states).
4. Regional variations in the behavioural response to the family planning programme are reflected in the age-sex composition.
Sources of Data and Methodology
Data for the present study has basically been obtained from the Census and Sample Registration system. From the Census, the Socio-Cultural tables of 1971, 1981, and 1991 have been taken as the basis of the age-sex data. From the Sample Registration System, fertility and mortality data of 1971, 1981, and 1991 as well as life tables of 1993-94 have been obtained to collect data on the expectation of life at different ages.
For the analysis of the data, simple tables giving percentage figures and other representative figures have been used. Besides, the data have been also represented through graphs such as bars and age-sex pyramids to show the changes in different age-cohorts.
Pattern of Change in the Age structure of India
The change in the age structure of India has been quite gradual since the first complete Census conducted in 1881. Since that Census, the data to study in detail the age structure of India’s population is authentically made available. The paper also examines, 2001 Census, which has been published recently.
Broadly, the age groups have been studied under three categories. The first one is 0-14 age-group, which is predominantly young age group largely dependent on their parents for their well-being. This age group contributes little but consumes more of the resources. The second one is of 15-59 age-group, which is the main working group. This group is the contributor to the national income by their labour. The third group is of population aged sixty plus. The first and the last group are demographically labelled as dependent population where as the middle one is the independent population. In this section, census data of the last twelve decades (since 1881) has been examined to identify the changes in the age-sex structure of India’s population.
The data reveals that India’s population in the 0-14 age group has remained close to 38-39 percent from 1881-1951. There was a sudden increase in 1961, when the percentage of population in 0-14 age group crossed the mark of forty one percent (41%) and in 1971; it reached its peak by crossing forty two percent (42%). This is evidently because of the decline in the mortality rate during this period and not due to a significant decline in the fertility rate. And then onwards, fertility has experienced a declining trend till date. Census 2001 data indicates that 0-14 age-group constitutes 35.35 percent of the total population which has been the lowest ever.
In 1881, the percentage of population in 15-59 age-group was 56.35. In 2001, it was little over 56.93 %. The lowest percentage of population in this group was in the year of 1971, when it dipped to 52 percent. In the census year of 1911, 1951 and 2001 there has been almost same percentage of population at about fifty seven percent. Since 1971, there has been continuous and uniform increase in the percentage of population in this age group.
60+ Age-Group
This age-group has been experiencing an increasing trend ever since 1881. There have been few census decades, which have shown interruption in the otherwise smooth trend. The lowest percentage of population (5.08) in this age group has been recorded in the year of 1901. In this year, the percentage of population in this age group was 5.08. In 1881, the percentage was 5.25 percent. There had been very slight differences in the percentage of sixty plus population till 1931. The proportion hovered around five percent. But, since 1941, there had been a continuous rise in the proportion of the elderly population. The maximum percentage in this group is recorded in the 2001 census. In this census year, the persons over 60 years of age were at 7.72 percent.
Age Structure in Detailed Age-Cohorts since 1881-2001
The trend in age-structure is further revealed through the analysis of detailed age-cohorts from 1881 to 2001. In the first two age-cohorts i.e., of 0-4 and 5-9 years, there is a decline in their proportion in the total population of India after 1961. This trend is maintained even in the 2001 census. The proportion of population in the 0-4 age cohort was the highest in the year 1961, when it reached 15.06 percent. The census of 2001 recorded the lowest proportion of population in the same age-group at 10.74 percent. In the 5-9 years age-cohort, the lowest proportion is recorded in the 2001 census. There is a sudden decline in the proportion in the year 1951.
In the 10-14, 15-19 and 20-24 years age-cohorts, fluctuations have been observed within a limited range with a tendency towards increase in the proportion of population in these age-groups since 1881. In the first age-cohort, the peak reached in the year of 1981, when it remained just short of thirteen percent. In the second age-cohort, the peak reached in 2001 census, when it was just below ten percent. In the third age-cohort (20-24 years), the proportion ranged between eight and nine percent, the peak having reached in 1991. The difference between the highest and the lowest proportion of population is very low in this age-cohort.
In the 25-29, 30-34 and 40-44 years age-cohorts, first we have declining trend and this decrease reaches its nadir at 7.45%, 6.35% and 5.07% in respective age-cohorts from where it again ascends. But, in all of these three age-cohorts the summit of the trend line is in the year of 1881. The proportion of population in these age-cohorts, hence, had its peak in 1881 and then onwards it declines only to increase during the latest census in the end of the studied period.
The age-groups 35-39 years, 45-49 years and 55-59 years show similar trends. In these three age-cohorts, the population has indicated increasing trend since 1881. It has its lowest proportion in the beginning of the trend line and highest in 2001. This trend is similar to 10-14 and 15-19 years age-cohorts, difference being in the smooth trend line in the former and the fluctuating trend line in the latter. Only difference among these three cohorts is the proportion. In the first, the proportion varies between five to seven percent. In the second, this varies between three to five percent and in the third, it varies from one to three percent.
In the 50-54 years age-cohort, the proportion of population has declined throughout the years under study. This trend is opposite to the immediate previous age-cohort. It has its highest percentage in the beginning of the trend line and the lowest in the end. The 60+ age-group has a totally unique trend in the sense that it had more or less smooth curve, with proportion ranging between five and six percent till 1971, and then it increases suddenly at a fast rate. In 2001 census, the proportion of population in this age group was highest ever at 7.72 percent. The data of the twelve census years reveals the pattern of demographic transition where, in general, there is decline in the first two age-cohorts and increase in the last age-cohort.
Change in the Age-Sex Structure of India
An analysis of the change in the age-sex structure in each census from 1881 to 2001 reveals that there is an increase in the base population (0-14 years of age group) in both the sexes. There is however, a decline in the other two age-groups i.e., 15-59 and 60 plus age-group in both the sexes, though this decline is very marginal. The population in both male and female declined in 1901 from 1891. In 1901, the 0-14 age group male population declined by 0.74 percent and female population declined by 0.80 percentage point. The proportion of decline in the old age population continued in 1901. But, there was some increase in the 15-59 age group population. Behaviour of individual age-cohort remained the same. In 1911, there was again a decline in the young age-group. In 1901, the 0-4 age group contributed in the decline of the young age group population. Change is observed in the decline was mainly because of 5-9 and 10-14 years age-group population during 1911. The 0-4 years age–cohort witnessed an increase in its proportion during the same period. There is an increase in the sixty plus population. In the productive (15-59) age-group, there is a decline in the proportion of the female population whereas an increase is recorded in its male counterpart.
In the year of great divide i.e., 1921, the male/female population behaved differently. There was a sudden decline in the proportion of male population, whereas, at the same time there was surprisingly increase in the female proportion of population. The only increase recorded in the male proportion was in the sixty plus age group and the only decline witnessed in the female proportion was in the productive age-group. The 5-9 age-cohort indicated a sharp decline in the male proportion and increase in the female proportion, which shows the aftermath of the calamity of the decade.
In 1931, the proportion of old age population declined in both male and female. There was increase in the male population in both the age groups, whereas there was decline in the proportion of the female population in all the three broad age-groups. In 1941, there was increase in the proportion of population in all the three individual age-cohorts. There was decline in the 15-59 years age group in both male and female. The old age population also registered an increase. In 1951, there was a surge in the proportion of working population. It was recorded highest in the entire census period. This proportion was almost revisited in 2001 census. There was a decline in the young age population in both male and female. During 1961 and 1971, there was increase in the proportion of young and old age population. In fact, the proportion of old age population has never shown downward trends since then in both male and female. Since 1981, there is continuous decline in the proportion of the young age-group population. Also, there is continuous increase in the proportion of the productive age group population since then. Hence, since 1961, there is a clear trend, which is almost in consonance with the trend in the birth rate and death rate.
Age Structure in the Northern and Southern States
In this section, an attempt has been made to study the age structure of two demographically contrast regions of India i.e., the four northern states of Bihar, Madhya Pradesh, Rajasthan and Uttar Pradesh (BIMARU states) and the four southern states of Andhra Pradesh, Karnataka, Kerala, Tamil Nadu. The BIMARU states have low socio-economic and demographic characteristics measured in terms of birth rate, death rate, infant mortality rate, sex-ratio, education, status of women etc. The four southern states reflect good demographic indicators. The four states in both the regions are combined together for age-sex analyses and are also compared with India as a whole.
Northern states are known for their poor demographic indicators. Their fertility rate, mortality rate, infant mortality etc. are very high, and life expectancy at birth is low. Whereas southern states indicate good demographic indicators. Kerala’s demographic indicators are at par with some of the developed countries of the world.
In India, the 0-4 and 5-9 age groups record a continuous decline in the proportion of population, whereas there is continuous increase in the proportion of the population in 55-59 and 60+ age-cohorts.
Similarly, in the southern states, there has been a decline in the proportion of the population in the 0-4 and 5-9 years age-cohorts. But, in the northern states this decline is not smooth and even the proportion remains at higher level than both of the other groups. In 2001, the proportion of the population in 0-4 age group in the southern states dipped below nine percent level, where as in northern states, it is still more than 12.5 percent.
Similarly, in 5-9 years age-cohort, southern states registered a continuous decline in the proportion of the population in their total population. But, northern states registered growth in proportion of population in the same age-cohort. In 2001, the proportion of the population in 5-9 years age-cohort was a little below the fifteen percent mark in the northern states, whereas this proportion in the southern states is at nine percent (9%) level. This trend is almost evident in all the age-cohorts. In all the three young age-cohorts, in northern states the proportion is far more than the southern states. Moreover, the declining trend has not begun even in 2001 census. In the productive age group population, there is a gain in the proportion of population in the southern states, but again there is reverse trend in the northern states. In sixty plus population, the growth in the proportion of population is lower in the northern states whereas, it shows an upward trend in the southern states.
In 1971, the proportion of population in young age cohorts has remained higher in the northern states, where as, it is lower in the southern states.
In fact, the proportion of population has always remained higher in the southern states in all other age-cohorts except the young age-cohorts in all the four different census years. The gap of proportion has steadily widened through successive census years. By the census year 2001, the difference of proportion between the northern states and southern states has become too large. It indicates that the pace of change in the two regions in India is not the same. It is rapid in the four southern states, whereas it is very slow in the northern states.
In this section, an attempt has been made to delve deeper into the change in the age and sex structure in northern states and the southern states from 1971 to 2001.
The figures reveal that the change in the age and sex structure in the northern states is almost negligible when compared with the southern states. In the young age cohort, the decline in the northern states is two-percentage points in the case of both male and female in the last four decades. This difference is as high as eleven-percentage points in the southern states in the case of female and of ten-percentage point in the case of male.
In the case of southern states, one can witness the shrinkage of the proportion of population in each age cohort through the successive decades. But, this is not the case with the northern states. There is instead an increase in some cases. During 1991 and 2001, there was an increase from 40.09 percent to 40.78 percent in the proportion of the male young age-group population. Not only this, there is a decline in the case of female working population in the northern states during 1991-2001 from 52.55 percent to 52.25 percent where it should increase. In the old age group again, the continuous swelling of the population was halted in 1991-2001. There was shrinkage in the case of male old-age population by almost 0.50 percent.
In 1971, the difference of proportion between both the regions in the young age group are of 3% in the case of male and of 2.25 percent in the case of female. In 2001, this difference widened enormously and reached at more than ten percent in the case of male and more than eleven percent in the case of female. Similar is the case with 15-59 years age-group. There is a difference of about two to three percent in both the regions and in both the sex group. This difference again amplified to the extent of almost nine to ten percent in both the sexes. In the sixty plus age group, the proportion of population in 1971 in both the regions was more or less similar; rather in the male population the proportion was bigger in the northern states than the southern states. But, by 2001, the scene again changed and proportion increased in the favour of the southern states.
Conclusion
The change that has taken place in the India’s age structure during the last one hundred and twenty years indicates a very slow trend. The time-lag of the change in different age-cohorts is much higher than some of the developed countries. India was one of the first countries in the world to implement family planning programme, but its effect has been rather gradual.
The spatial pattern of occurrence of change in the age structure is again at variance. Some states have witnessed faster change in the age structure of population than the others. As it has been hypothesized that the reduction in the proportion of population in the younger age cohorts is taking place because of the decline in the fertility is true only in a few developed states, while in others, a threshold decline in the fertility is still to take place before its impact is felt on the age-sex pyramids. There is indeed an increase in the proportion of old age population; yet, the southern states have witnessed faster growth in the proportion of the sixty plus age cohorts than the northern states. Overall, the growth in the proportion of sixty plus population is moderate. Hence, the hypothesis that changes in the age-structure are more pronounced in the demographically developed states (southern states) than demographically under developed states (northern states) is testified. The northern states are not yet responding substantially well to the family planning programme.
The change in the productive age-group is of prime importance in the study of any age structure. It has been seen that the proportion of productive age group, remains more or less stable at fifty-five percent. It declined to fifty-two percent (52%) in 1971, but again it increased to the level of fifty seven percent in 2001. The change has been rapid in the southern states than in northern states.
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