As the Nation Grows Younger
The acceleration of our birth rate has had the experts guessing since the end of the Second World War. FRANK NOTESTEIN, director of the Office of Population Research at Princeton University, reports on this phenomenon and discusses what it will mean to oar country in terms of jobs, opportunities, and standards of living.
THE population of the United States has begun to grow younger. Individually we grow older with ever-increasing chances of survival, while collectively we have started to grow younger for the first time in our national history. The reason for the trend is of course the spectacular increase in the number of births since the war.
This collective drift to younger average ages will have a host of repercussions on the temper of our life. Indeed, these repercussions are being felt already in new pressures for schools, houses, and the sharply expanding urban development. As the younger groups gain predominance in the total population figure, will our economy become more dynamic and will our leaders in industry and government take over at an earlier age?
This trend to a younger average age is new in the Western world. Our populations had been getting older for a long time, and alter 1930 they had been aging very rapidly. In the United States half of the population was under 17 years of age in 1820. The median age began to rise and had climbed above 25 by 1920. It was at a maximum of 30.2 in the early fifties. By 1956 it had fallen lo 29.9, and there is a possibility that it will fall below 26 by 1975.
These small movements in the median age reflect rather marked shifts in the groups that are economically important — shifts that change the dependency loads of youth and old age and the balance of our labor forcc. It will be useful to see what they have been, how they have come about, and the ways in which they seem likely to move in the future.
The proportion of young dependents in the population declined progressively until 1950, when only 34 per cent of the population was under age 20. Then the mounting birth rates of the post-war years brought a reversal of trend, and by 1956 the figure had risen to 37 per cent. Meanwhile there had been a steady rise in the proportion of the aged. The proportion in the middle groups, from which the labor force is mainly drawn, rose steadily to a maximum of 59 per cent in 1940, and fell sharply between 1950 and 1956, when it amounted to only 54 per cent. This shrinking proportion in the working ages has probably been a considerable factor in minimizing unemployment during the post-war years.
Sharp changes in the rate of population growth have accompanied these shills in age structure. In 1950 our population was twice as large as it was in 1900, yet until 1940 the rate of growth had been slowing. The rate rose a little before and during the war and then shot up with surprising speed By the middle of 1956 the population had reached 169 million and was growing at an annual rate of 1.7 per cent. Such a rate is sufficient to change the character of our country in a short time. If it were to continue, a large majority of the children born last year would live long enough to see us a nation of half a billion people.
Before considering future possibilities, let us look more closely into the sources of past changes in our growth and age structure. The reduction of the death rate has been spectacular. It is hard to realize that, on the life table for 1954, a newborn white girl has a better chance of surviving to age 60 than she had of living to age 5 under the health conditions prevalent at the beginning of the century.
The average expectation of life at birth for white females rose from 51 years in 1901 to 74 in 1954. This improvement in longevity is sufficient to increase by nearly one half the size of the population that a given stream of births will maintain. The postponement of death has been a major support of our rate of growth.
It is widely believed that the lengthening expectation of life has also been responsible for the rising average age of the population. Long life for the individual, it is argued, must tend to give us an old population. Reasonable as this view seems, it is untrue. Improved chances of survival have tended to lower the average age slightly, as my colleague Ansley J. Coale has shown. And all ages in the span of life have shared in the improvement.
If the improvement were of equal proportions — say a 40 per cent increase — the age structure would be unaffected. Such a change would increase the rate of growth, but it would do so equally in all ages. In fact, since 1900 the improvement has been somewhat disproportionately large in the youngest ages, thereby particularly stimulating population growth in those ages. Changes in mortality since 1900 would have made our population slightly younger if nothing else had happened.
Meanwhile, however, our birth rate fell almost continuously, as part of a decline extending from the early nineteenth century to the late 1930s. It is this decline that checked our rate of growth and lifted the average age of the population. The birth rate began to rise a few years before the war, kept rather high during the war, and has been amazingly high throughout the post-war period. The story of its changing course is fascinating and has puzzled those of us who live with such figures.
The wartime revival in births had been interpreted as the product of an unusual situation that would soon pass. There had been a sharp decline in the age at marriage. The emotional pressures of the war, family allowances for men in the services, and general prosperity were stimulating early childbearing. But there was no evidence that an increase in the size of completed families was under way. The size of families had been falling for many decades, and a deeply probing investigation carried out just before the war strongly suggested that this trend was likely to continue. The wartime rise in births was, therefore, viewed as a shift to younger childbearing rather than as an increase in the number of children. It was thought to foreshadow not further increases in births, but a rather sharp decline.
The evidence leading us to expect a decrease in births after a post-war spurt seemed convincing to me, but instead of a decline there was a positive flood of births which has continued to the present time. Incredibly, from the point of view of a decade ago, the birth rate of the United States, at 25.3 in 1956, was higher than the birth rates of such traditionally fertile nations as Italy, Spain, Portugal, and Japan.
Interestingly enough, this post-war rise has been generally larger in urban than in rural areas, and in the upper than in the lower educational and occupational groups. As a result, the former regional, educational, and occupational differences in birth rates have been much reduced. It is to be noted that the rise has been most pronounced in precisely those sectors of the population that, in other circumstances, have shown their ability to restrict their childbearing quickly and effectively.
THE significance of the 1956 experience is not entirely clear. If we imagine a group of women bearing children as they move through life at the rates at which women of corresponding age bore children in 1956, such an imaginary group would have an average of about 3.7 children apiece, or about 3.9 per married woman. This is a very high figure, suggesting perhaps that the recent rates of childbearing will not be sustained throughout the life of any actual group of women. Indeed, no actual class of women born in this century has produced as many as three children on the average. All of the classes in the childbearing ages are now well ahead of their immediate predecessors. The rise in family size is already achieved. But unless women continue to bear children much more rapidly than any experience of the present century would suggest, they will not attain any such average as 3.7 children.
The Office of Population Research at Princeton University is now conducting a rather intensive field inquiry concerning many of these matters. Data from it are not yet available but we do have the results of a pretest made in one metropolitan area. The wives interviewed were native white and had borne their second child a few months prior to the interview.
No one can read the records of these interviews and fail to be impressed with the genuine revival of interest in family life and children. The impression is wholly different from that given by similar records taken early in the 1940s, when the typical parents could scarcely imagine the circumstances that would make them want more than two children. In our small sample, which is far from a representative sample of the nation, about two thirds of the wives look forward to having three or four children, and those who want only two children tend to be apologetic about the small number. Lew parents have qualms about being able to support and educate their children. Indeed, if all the children go to college whose parents plan to send them, we face the need for a staggering expansion of facilities lor higher education. Nor is it all talk. A substantial proportion of these parents already have started savings accounts or insurance policies to provide for their children’s college education despite the fact that their older child has not even started elementary school.
It is too early to have more than preliminary hints from this study, but it is perhaps worth noting that Catholics appear to want more children than Protestants. Among both Catholics and Protestants, the parents who attend church regularly tend to want more children than those whose attendance is infrequent. There are also indications that the families wanting more children tend to be in the white-collar classes and well educated. They have fair incomes, are reasonably happy in their work, and are personally well adjusted. This is a very different picture than would have emerged in any metropolitan community prior to the war.
What the situation bodes for the future is not clear. One gets the impression of an element of conformity and pattern. Parents are now planning to have children because they want them, and not because they think them unavoidable. The large majority are practicing some form of voluntary restriction. We have, therefore, a demonstration that it is possible for a highly developed urban-industrial society to produce a setting in which parents will want enough children to support rapid population growth. The somewhat widespread fears of the depression decade that urban-industrial life and universal birth control would necessarily bring declining populations have been dissipated.
Nor is there occasion to swing to the opposite view that we are moving toward the re-establishment of the large-family system which characterized our early nineteenth century and characterizes most of the world’s peasant societies today. The present situation represents only a larger version of the small-family system and one that yields birth rates much lower than those of the underdeveloped areas today. The existing situation may not continue indefinitely. Given a new set of strains or a new shift of standards, perhaps as suburbs outgrow themselves, parents could reduce their childbearing quickly. For the immediate future, however, there is no sign of a sharp drop in fertility, although birth rates may decline somewhat, simply because women of childbearing age are forming a smaller proportion of the total population.
The future course of migration will also influence both our rate of growth and our age composition, but unless past restrictive policies are relaxed the effect will not be large.
We must now consider the bearing of the foregoing discussion on the future trends of growth and age composition. The accompanying charts present the highest and lowest projections issued by the Bureau of the Census. These results should be thought of as illustrating the consequences of specific assumptions about future trends in fertility, mortality, and migration. If the reader does not approve of the assumptions, he can introduce his own modifications to see at least the direction of change that they would yield. Both the “high” and “low” projections assume something over a million immigrants in successive five-year periods, and a continuation of the downward trend of mortality until 1960. The high projection assumes that the fertility rates of 1955 will continue until 1975. The low projection assumes that fertility will decline to the pre-war level by 1975.

As may be seen from Figure 1, the high projection gives us a population of 229 million by 1975, representing an increase of 63 million over the 1955 figure. A projection made in our office at Princeton, which assumes the maintenance of fertility at the 1956 level and a continued improvement of mortality until 1975, implies an increase of 70 million and a total of 236 million by 1975. Even if fertility should fall drastically by 1975, as in the low projection, the population would still increase by 42 million and reach a total of 208 million by 1975. The high projection drops the median age to 25.8, only a little above the figure for 1920, and even the slower growth of the low projection carries the median below 29 years. It is difficult to find an assumption, apart from that of major catastrophe, under which the next two decades can bring anything but rapid growth and a trend toward a younger population.
The peculiar age distribution from which the projections start in 1955 will have important effects as the survivors move on in age. This 1955 distribution is shown in Figure 2. The large numbers under age 10 represent the survivors of births in the past ten years plus a few immigrants. The trough from ages 10 to 30 reflects the small number of births from 1925 to 1945, and the relatively large number over age 30 reflects the larger birth classes before 1925. We can see one of the reasons for the high rates of pay being offered to workers just out of school in the small numbers aged 15 to 25. The high income that scarcity brings to them doubtless helps to explain the frequency of young marriages. Small numbers, which are further reduced by the prevalence of higher education and early childbearing, help to account for the current shortage of stenographers.

By 1975, the trough in the age distribution lies between ages 30 and 50, as may be seen from Figure 2. The population between 35 and 45 is smaller than at present. Above age 45, however, the gains are very large, and between 20 and 30 they are even larger. Ages 20 to 25 have 9 million more people in 1975 than in 1955, representing an increase of 79 per cent. By 1975 there should be no dearth of entering workers. Quite possibly the large supply will check wages for young people, curtail marriages, and cut the birth rate. College graduates may even be a dime a dozen.
The group aged 15 to 20, which is of special interest to high schools and colleges, will increase about as rapidly as that aged 20 to 25, if the birth rate stays high until 1960. It rises from 11 million to 20 million on the high projection, or about 81 per cent. With the trend toward universal higher education, it is possible that the increase in students between 1955 and 1975 will be several-fold.
If fertility follows the high assumption until 1975, the number under age 20 rises to 93 million, which is well above the total population of 1900. It represents an increase of 32 million over the 1955 figure. Even if fertility falls sharply to its pre-war level, the population under age 20 would increase by about 11 million between 1955 and 1975, reaching a total of about 71 million at the latter date. Both alternatives have a dip at ages 10 to 15 in 1975 that echoes the older trough as it moves through the childbearing years. The same situation is reflected in the projected course of the birth rate shown in Figure 1. The most notable effect of the low fertility assumption is the magnitude of the new trough that it would introduce into the age distribution.
WHATEVER the future course of the birth rate, within the limits considered here, it is evident that our population will increase rapidly, that growth will be most rapid among the old and young ages and least rapid in the middle range, and that we shall have a declining average age. The growth and shifting balance of the age groups are bound to have important economic consequences. Among them we must distinguish two types: one relating to the level of economic activity and the other to the productive balance at any given level of activity.
So far as the future level of economic activity is concerned, the demographic situation in the near future looks highly favorable. Growth undoubtedly tends to stimulate economic activity in a wealthy country that at times has experienced difficulties in maintaining a sufficient demand to utilize fully its productive facilities. The task of providing the goods and services that will be required in the next twenty years for an expansion ranging from one quarter to one third or more of the present population should give no small amount of stimulus to the economy.
When, as in our case, this growth is especially rapid outside the working years of life, the stimulus to the labor market should be particularly strong. This trend is marked between 1955 and 1965. In the census projections the population outside the working ages grows from two to three times as fast as that between 20 and 65 years. Until 1965 the slow growth of the working ages should furnish a powerful buffer to the risks of unemployment that might come as automation replaces both industrial and clerical workers. Indeed, thanks to our peculiar age structure, we may go far in achieving the productive gains of automation without a major disruption of the economy.
From 1965 to 1975 the situation is less clear. By that time the huge birth classes of the postwar years are entering the labor force. Even so, if fertility stays high, the increase outside the working ages will be more rapid than that in the working years. If, however, fertility should fall, as in the low projection, persons of working age would increase about four times as rapidly as those in the dependent ages. Given this course of events, the contrast between the two decades would be extremely sharp and require major economic readjustments.
FLEXIBILITY will be needed to meet this rapid shift from a scarcity to an abundance of young workers, but the demands of growth itself may go far toward producing that flexibility. We can only speculate about the changes in the spirit of the times that may come as our center of gravity and leadership shift toward youth. With our problems of stark poverty essentially solved, shall we simply go on to progressively higher standards of living with ever-heavier drafts on our own and the world’s resources? Or will the outlet for new energy come in leisure, and if so of what nature? Will it carry us to new levels of education and cultural achievement? Or will the expanding energy be channeled into new efforts to meet world-wide responsibilities? No one can be certain of the answers but, given peace, our youth growth and productive power provide a dynamic combination that is certain to find exciting outlets.
A word of caution is necessary about the above line of argument. It leaves too many factors out of account. By no means are all of the elements associated with population growth fortunate for the nation. Space for living and recreation will Be in progressively short supply, and privacy progressively expensive. Escape from the city will become increasingly difficult as suburbs grow into cities. Shorter working hours may well be canceled by longer hours of travel between home and work. Many standards of quality will decline as pressures for quantity rise. Whether one views progressive crowding as fortunate or unfortunate is largely a matter of taste. The frontiersman thought that two persons per square mile represented intolerable crowding, whereas the resident of Europe or Asia finds our land almost empty today. Undoubtedly, as growth goes on, our own standards will change. Speaking for myself, however. I should prefer the qualitative opportunities that go with slower growth and smaller numbers.
A considerable part of the stimulus arising from the prospects for rapid growth appears to be psychological. We seem to be greatly impressed by the tangible growth in numbers and insufficiently impressed by a host of other factors that can bring economic expansion. The demand for goods and services could easily fall in spite of rapid population growth; and, conversely, it could rise rapidly with only a slow population growth. Population growth provides some stimulus to the economy, but a general belief that it is very important intensifies the effect.
Perhaps because of our experience with depressions, we tend to be preoccupied with the problems of maintaining economic activity to the neglect of other equally important elements of prosperity. Such matters as the ratio of workers to dependents and the relation of total numbers to resources and living space are of basic importance. In fundamental terms the argument based on economic activity is a curious one. Our economic prospects appear to be favorable because we shall have to devote our productive energies to providing for additional tens of millions. Indeed, the prospects are viewed as particularly bright because this rapid expansion has to be undertaken by a population of working age that is increasing very slowly. In short, they are bright because the load on the productive ages is going to get heavier. The situation is anomalous in the extreme. Instead of counting on population growth to serve the needs of the economy, we ought to give more attention to the ways in which the economy could be made to serve the needs of the population.
In the immediate future this preoccupation with the need for youth and growth to maintain prosperity does not seem to be particularly dangerous. The nation is getting much pleasure from its new abundance of young life. In the long run, however, the situation may become serious. We cannot stay young without growing, and we cannot grow indefinitely without paying the penalties of huge size. The low census projection gives 208 million in 1975; the high, 229 million. Maintenance of the fertility of 1956 would carry us to something like 236 million. Short of catastrophe, it is difficult to see the terms on which we shall be much under 300 million by the year 2000, and a continuation of last year’s rate of growth to that date would bring us to almost 360 million.
THE United States is one of the very few highly developed countries in which the population is growing younger, but the trend toward growth and youth is typical of the underdeveloped nations of the world. Rapidly falling death rates, coupled with birth rates at least 60 per cent higher than our own, are stimulating growth throughout the underdeveloped parts of the world and increasing the already heavy burdens of child dependency. It is characteristic of such countries to have more than 40 per cent of the population under 15 years of age.
In our case, we may welcome the trend toward growth and youth at least for a time. As the world goes, we are not yet heavily populated. We have rich natural resources, a highly developed economy, a technologically skillful labor force, and ample capital. The trend toward growth and youth has an entirely different meaning where almost all of these assets are lacking and the population densities are already enormously high, as for example in China, Egypt, India, and Java. For them the new growth and added burden of young dependents represent a heavy drag on their struggle for improved living conditions. The Only way in which they can ease their burdens, while retaining their gains in health, is to cut the birth rate. A number of them, including India, China, and Egypt, are beginning to bend their efforts in this direction.
A huge accretion in numbers, such as that implied by the continuation for several decades of our present rate of growth, would put an enormous strain even on our own relatively rich resources. Undoubtedly, technological advance will do as much to ease the strain in the future as it has in the past. We could doubtless absorb such growth without reducing per capita income. Whatever the technological situation may be, the smaller population size gives us more raw materials per capita with which to make our living. Before many decades we must balance the advantages of youth and growth against the liabilities of an enormously congested country. Without growth, the only way for a population to stay young is to die early. If we are to avoid unending growth, the population, like its individual members, can live longer only by growing older.