On the distribution of completed parities when fertility is heritable

"Over the last one hundred years, there has been, in many developed countries, a demographic convergence towards the two child family. The possible implications for population growth of such a tendency are considered in this paper in terms of both family limitation and also the intergenerational transmission of fertility. These two effects interact so that as the proportion of two-child families increases, the possible influence of mother-daughter fertility associations on population growth decreases, though even now it could override otherwise significant changes in either or both of the birth and death intensities. In particular, it is shown that according...to how fertility is transmitted through generations, it is still possible to have zero growth rates consistently with a widely dispersed stable distribution of family size as well as a typical mortality regime." (SUMMARY IN FRE)     

Population growth with variable family size

The Sharpe‐Lotka continuous time deterministic model of population growth is developed to take account of some possible forms of mother‐daughter fertility association, characterised here by a bivariable measure, A. This leads to a linear double integral equation for which, subject to certain conditions, a finite time solution can be found by Laplace transform methods and thus also model specific results relating the intergenerational fertility effect to the long term population growth rate and magnitude are established. The quantitative implications of the theory are illustrated by a consideration of a general bilinear form of A and in this context numerical results illustrating the finite time growth and also the long term distribution of fertility levels in the stable female population are obtained. In particular, it is shown that different fertility specific subpopulations can coexist indefinitely.     

Options for Fertility Policy Transition in China

This article compares five currently debated scenarios for fertility policy transition in China, in terms of their implications for future population growth and population aging, the proportions of elderly living alone, labor force trends, pension deficits, economic costs, the marriage squeeze, and other socioeconomic outcomes. Based on these comparative analyses, the author concludes that China needs to begin a gradual modification of its fertility policy as soon as possible. He proposes a three‐stage “soft‐landing” strategy for fertility policy transition: (1) a 7‐year initial smooth transition period; (2) from approximately 2014‐15 to 2032‐35 a universal two‐child policy combined with late childbearing in both rural and urban areas; (3) after 2032‐35 all Chinese citizens would be free to choose family size and fertility timing. This strategy will enable China to have much more favorable demographic conditions and socioeconomic outcomes, as compared to keeping the current policy unchanged.     

Books and publications received

Efforts to control rampant population growth in sub-Saharan Africa have been stymied by confusion between the potential causes and consequences of high fertility in the region. A controversy has surfaced over the causal direction of the fundamental relationship between human fertility and size of landholdings. Members of one school of thought claim that farm couples modify their fertility behaviour according to the amount of land they own or operate. Yet others argue that the size of landholdings varies as a function of family size (an indicator of the availability of family labour). In the present study we use a two-stage least-squares regression on data from a 1988 survey of 747 farm households in Rwanda to disaggregate and compare the strengths of these two possible paths of influence. The results show that landholdings exert a positive influence on human reproduction, but not the reverse. Moreover, this influence is slightly stronger for couples who own all the land they operated, probably because they have larger incomes from equity in the land. The size of the farm is unrelated to the size of the family's potential farm labour force (measured as the number of household members aged 15–65) or to the husband's total desired number of children. These findings suggest that farm size boosts the number of living children not by creating a demand for more children but by increasing the supply of children through higher natural fertility and child survival.     

The evolution in China's fertility and an analysis of population development]

There have been numerous projections on China's population at the end of century. Their differences are due to different estimations on the effects of fertility determinants. 2 simulation models have been developed, both from micro and macro levels, to estimate the population at the end of the century on the basis of 6 different fertility patterns. 3 possible options for fertility patterns are discussed. 1.) The 1 child per family option means that every couple has 1 child by the year 1989, the population of China will be 1.2 billion in the year 2000. Even if this is a ideal situation, it would not be a feasible policy, as the pressure from the rural population to have more than 1 child has been increasing in recent years. Nevertheless, it is still possible for urban couples to accept having only 1 child. Therefore, encouraging more people to have 1 child should be held as a basic policy. 2.) Under the option of 2 children per family with 2 or 3 years of spacing, the total population in the year 2000 would be 1.2 - 1.4 billion, which is unacceptable in terms of the development situation. 3.) Following a differential fertility policy towards urban, rural, and minority populations would mean that urban couples would have 1 child, rural couples whose first child is a girl or those who are in special circumstance would have 2 children. Minorities would have 2 or 3 children. AMong the above options, number 3 is more likely to be achieved in view of current socioeconomic, cultural, and demographic factors.     

How responsive is U.S. population growth to immigration? A situational sensitivity analysis

There has been public concern about the effect of immigration on population growth in the U.S. But how responsive is population growth to immigration? This paper examines the sensitivity of intrinsic population growth to immigration and situates such sensitivity in fertility and survival changes. The application of second derivatives on a modified Leslie matrix facilitates the analysis of situational sensitivity of U.S. population growth to immigration. The results show that the sensitivity to immigration is not as influential as the sensitivity to fertility, and that the sensitivity to immigration further depends on changes in fertility and survival.     

The multistate stable population model with immigration

This paper outlines the discrete‐time and continuous‐time formulations of the stable population model with immigration, showing their commonality. It then illustrates how the model can be extended to include multiple interacting populations, and goes on to consider a multistate version of reproductive value that further illuminates the evolutionary dynamics of an “open”; model of multistate population growth and redistribution. Attention is restricted to results arising from a fertility regime that is below replacement level.     

The need for family planning

The purpose of this paper is to examine the evidence on the need for family planning. The available evidence on current levels of unmet need for contraceptives, fertility preferences, and the non-contraceptive benefits of family planning is reviewed. I argue that expansion of family planning programs is still needed. These programs provide couples with tools to reach their desired family size; can significantly impact maternal and child mortality by decreasing fertility and optimizing child spacing; and by decreasing fertility, slow population growth. It is therefore imperative to continue to expand the provision of family planning services.     

Second Births and the Second Shift: A Research Note on Gender Equity and Fertility

In a set of propositions on fertility transition, Peter McDonald recently proposed that the decline from replacement‐level fertility to low fertility is associated with a combination of high levels of gender equity in individual‐oriented institutions, such as education and market employment, and low levels of gender equity in the family and family‐oriented institutions. Similarly, the “second shift,” or the share of domestic work performed by formally employed women, forms a critical piece of current cross‐national explanations for low fertility. Building on this scholarship, the authors explore whether there is empirical evidence at the individual level for a relationship between gender equity at home, as indicated by the division of housework among working couples with one child, and the transition to a second birth. Results, based on a sample of US couples, indicate a U‐shaped relationship between gender equity and fertility. Both the most modern and the most traditional housework arrangements are positively associated with fertility. This empirical test elaborates the family‐fertility relationship and underscores the need to incorporate family context, including gender equity, into explanations for fertility change.     

R. F. Harrod on Reviving the Birth Rate

Continuing below‐replacement fertility and projected declines in population size are demographic features of many European countries and Japan. They are variously met with complacent acceptance, calls for higher rates of immigration, or—often last and least—proposals for increasing the birth rate. Fertility was also low in the 1930s, and some of the policy debate from that period resonates today. In England and Wales, fertility then had been declining for half a century. Over the decade 1931–40, it averaged 1.8 children per woman—moreover, with net emigration. Worries over this situation and its likely consequences led to the setting up in 1944 of a Royal Commission on Population, charged with considering “what measures, if any, should be taken in the national interest to influence the future trend in population.” In a memorandum submitted to the Commission in that year, the economist R. F. Harrod set out a detailed proposal to encourage childbearing through a scheme of family endowments. Part of the introductory section of Harrod's submission, arguing the case for state intervention and for material rather than ‘spiritual’ measures, is reproduced below. An evident problem in offering economic incentives for childbearing is that, to induce a given behavioral change, well‐off families would require much larger incentives than the poor. Hence child endowments that aspire to effectiveness across the income distribution have to be skewed toward the upper end. Harrod argues that this is as it should be, that policy should establish neutrality between large and small family sizes, and that this is a conceptually separate issue from poverty alleviation. ‘We should seek a re‐distribution of national income favourable to the parents of larger families and the plan should be put into effect whether or not another re‐distribution as between rich and poor is proceeding at the same time.’ He remarks on the implausibility of the government's being able to ‘talk up’ fertility— thereby generating some kind of costless ideational change, a ‘spiritual aufklärung.’ Later pans of the submission not reprinted here cover the specific details of the proposal. The proposed annual benefit per child (intended for every child after the second, with half‐rates payable for the second child) is paid for 18 years. It is substantial and increases with the child's age—at ages 13–18, for most of the income range it amounts to 20–30 percent of the father's income (or mother's, if hers is higher). Harrod also discusses further the rationale for making the endowments (and the compulsory contributions—a flat 5 percent of income—that finance them) proportional to income. To make his case Harrod draws on the dysgenic and population‐quality arguments popular at the time: worry about ‘race decline’ and ‘a general lowering of standards and of efficiency if the parents who are best equipped in experience, knowledge and culture are relatively infertile.’ In the event, the Commission recommended a flat schedule of family allowances, together with tax exemptions for dependent children calculated to provide some income‐based benefit. These were justified on population as well as equity and welfare grounds, ‘since the handicaps of parenthood have played a large part in the fall of average family size below replacement level.‘ Population quality issues—the subject of several other submissions—were sidestepped by calling for further research. By the time the Commission's report was finally published, in 1949, the baby boom was well underway: average fertility over 1946–50 was 2.4. Roy Forbes Harrod (1900–78) was one of the foremost economists of his day. His career was largely spent at Christ Church College, Oxford. A student and sometime colleague of Keynes, his best‐known early work was centered on identifying a dynamic equilibrium growth path for the economy—building on Keynes's static equilibrium analysis. As stylized (by others), this came to be called the Harrod‐Domar growth model, a formulation basic to growth theory. Harrod was editor of the Economic Journal for the period 1945–66. He was active in politics and as an economic adviser to both Labour and Conservative governments. He was knighted in 1959. The extract is reprinted from volume 5 of the Papers of the Royal Commission on Population (London: His Majesty's Stationery Office, 1950), pp. 80–85.     

Closing a Sociodemographic Chapter of Chinese History

At its recent Fifth Plenary Session held in Beijing, the Eighteenth Central Committee of the Communist Party of China decided to abolish the one‐child policy and allow all couples to have two children, thus closing an important chapter of China's social and demographic history. Recent fertility trends make it clear why it is urgent to abandon this policy. Census and survey data show that China's TFR had already fallen below replacement in 1991. Since the mid‐1990s, TFRs in most years have been lower than 1.5 children per woman. Since 2010, even lower fertility rates have been recorded by the annual population change surveys. Since the mid‐1990s, fertility decline has been increasingly driven by generalized ideational changes resulting from the social, economic, and cultural transformation of recent decades. In recent years many couples who were entitled to have a second child have chosen not to do so. For this reason, the termination of the one‐child policy is unlikely to lead to a major upturn in fertility, but rather to the continuation of a low‐fertility regime with more diverse fertility patterns across different sub‐populations, a pattern that has been observed in many countries.     

A stochastic version of the malthusian trap model: Consequences for the empirical relationship between economic growth and population growth in LDC's

A stochastic version of the Malthusian trap model relating the growth rate of income per capita to the population growth rate of a given country is described. This model is applied to the a priori evaluation of the cross‐sectional correlation between these two growth rates under two additional assumptions: i) the relations in the model at national levels include country‐specific and time‐invariant random components, and ii) these growth rates are measured with a certain degree of temporal aggregation. It is shown that these two assumptions can explain near‐zero correlations between the two growth rates even if there exist a strongly negative effect of population growth on economic growth. However it is not clear whether these assumptions fully explain such insignificant correlations. Indeed, the implementation of the model is complicated by the structural shifts which are likely to occur in the equations over the course of the demographic transition.     

Stabilization,birth waves,and the surge in the elderly*

Substantial regularities characterize the transition to stability that follows a shift from one set of vital rates to another. The new vital, rates interact with the population's initial age composition and generate birth waves whose amplitude and attenuation depend on the ratio of ultimate to initial growth and on the new pattern of stable net maternity. A greater change in growth and a later stable net maternity pattern produce larger fluctuations in the number of births. Stabilization begins at the youngest ages and proceeds upward. Sixty years after the shift, the birth waves have largely disappeared and the proportion under age 15 approximates the stable level implied by the new rates. Those patterns are manifest in the stabilization of both observed and Coale‐Demeny model stable populations.

When fertility falls, the new stable population has a larger fraction at all ages above (approximately) 30, with greater changes characterizing the extremes of life. Fifteen years after the fall, there is a trough in the number at ages 0–14. Sixty years after the fall, when the largest pre‐decline cohort is age 60–74 and the smallest post‐decline cohort is age 45–59, there is a surge in the relative size of the elderly population. Thus after two generations, the birth waves produced by a rapid decline in fertility accentuate the effects of population aging.     

Statistical modeling of selected aspects of the childbearing process with application to world fertility survey countries∗

The childbearing process should be monitored in developing countries experiencing high population growth rates and high levels of maternal and infant mortality. A mathematical model for estimation of certain aspects of the childbearing process, which requires only data on age‐specific fertility rates, is developed. Synthetic maternal childbearing indices, namely, mean ages at first and last birth, length of reproductive life span, inter‐birth spacing, and proportion of childless women, in addition to the well‐known mean age at childbearing, for the WFS countries are obtained using the proposed model. The indices are free from age truncation effects, and, under certain assumptions, provide information about a cohort's completed fertility before the women stop reproducing. The effects of women's residence and education on fertility are also examined.     

Turbulent dynamics in a Xviith century population

A reconstruction of the population of the Pays de Caux (1589–1700) yields the time series of a fertility behavior indicator, the overall Coale index If. In spite of the noisy appearance of its evolution, the trajectory of If looks ordered, as if it were confined alternatively to two given zones, looping in each of them for a while, then suddenly jumping from the low one to the higher one, or slowly whirling down from the high to the low one.

An attempt is made to explain this general temporal structure by using a simulation model based on the autoregulation model (the so‐called European Marriage Pattern), putting into play a choice of the spouse function, a fertility function, modalities of marriage and remarriage, under the environmental forcing of the reconstructed mortality conditions.

The correspondence between reconstruction and simulation turns out to be quite good, not only for the population size or the Coale index, but also for the marriage series, quite independently of the reconstructioa

A second simulation with simulated mortality conditions shows a bifurcation point: as the mean frequency of crisis increases, the state of the system leaves the lower level and concentrates more and more in the higher level.

Thus, not only does the autoregulator model appear validated by empirical data, but its bi‐modal structure is revealed, depicting the dynamic response of a traditional community both to the environment and to the endogeneous demographic process.     

The child survival hypothesis

Summary Because of current interest in the child survival hypothesis, we have reviewed available evidence bearing upon the relationships of infant and child mortality to fertility and contraceptive behaviour. The evidence is drawn from time series data for local and national vital events, from special in-depth studies of the infant mortality-fertility relationships in family formation, and from service statistics from health and family planning programmes. As a result of this review, we suggest five clarifications which should be made in redefining the child survival hypothesis and assessing its potential programme implications. The child survival hypothesis states that improved child survival will contribute to increased family planning motivation and consequent fertility decline. The evidence presented here suggests that the effect is not automatic and probably not a necessary pre-condition for fertility decline. There is certainly not a reflexive one-to-one replacement, but a partial effect may still be important. In the clearly demonstrated reduction in inter-pregnancy intervals after a child death, the major component is undoubtedly the removal of the biological protection of lactational amenorrhoea. A separate but somewhat smaller effect has been demonstrated in situations where lactation did not seem to have been the explanation. It is expected that increased child survival will contribute to fertility decline mainly in countries experiencing rapid mortality decline and population growth. The replacement of children who die is probably not so much 'volitional' as a result of alterations in sub-conscious expectations. It is apparent that in traditional agrarian populations, few direct and manipulable means of influencing motivation for fertility limitation are available, and, therefore, it must be stressed that integrated health and family planning programmes do provide opportunities for immediate programme development. By making parents aware of improved changes of survival through health services in which they develop confidence, the spontaneous linkages between mortality and fertility can presumably be reinforced. Family planning services must be provided as an essential initial step in programme development, but they can be made more effective, as well as politically more acceptable if appropriately integrated with maternal and child health and nutrition services.     

独生子女大规模进入婚育年龄对我国人口发展的影响

大规模的独生子女进入婚育期以及我国差异化的人口控制政策,必然使政策生育率上升。其后果主要表现为：一、理论上每年出生人数增加约160万。使我国人口峰值提高了约4800万;二、弱化我国人口政策的区域差异所导致的人口素质“逆淘汰”,加快人口素质的提高,同时长期偏高的出生性别比也将得到一定程度的缓和;三、城镇将出现大量的“四二一”家庭,而且家庭空巢阶段也将提前到来,空巢家庭比例快速上升。     

Thinking about several problems of the research of our family planning strategy]

On the basis of 1982 census data, it is estimated that from 1987-1997 13 million women will enter the age of marriage and child-bearing each year. The tasks of keeping the population size around 1.2 billion by the year 2000 is arduous. Great efforts have to be made to continue encouraging one child/couple, and to pursue the current plans and policies and maintain strict control over fertility. Keeping population growth in pace with economic growth, environment, ecological balance, availability of per capita resources, education programs, employment capability, health services, maternal and child care, social welfare and social security should be a component of the long term development strategy of the country. Family planning is a comprehensive program which involves long cycles and complicated factors, viewpoints of expediency in guiding policy and program formulation for short term benefits are inappropriate. The emphasis of family planning program strategy should be placed on the rural areas where the majority of population reside. Specifically, the major aspects of strategic thrusts should be the linkage between policy implementation and reception, between family planning publicity and changes of ideation on fertility; the integrated urban and rural program management relating to migration and differentiation of policy towards minority population and areas in different economic development stages. In order to achieve the above strategies, several measures are proposed. (1) strengthening family planning program and organization structure; (2) providing information on population and contraception; (3) establishing family planning program network for infiltration effects; (4) using government financing, taxation, loan, social welfare and penalty to regulate fertility motivations; (5) improving the system of target allocation and data reporting to facilitate program implementation; (6) strengthening population projection and policy research; (7) and strengthening training of family planning personnel to improve program efficiency.     

Does low fertility call for new policies in some Asian countries?

Over the past 2 decades, Japan, China, Singapore, Hong Kong, and South Korea have completed a demographic transition from high birth and death rates and runaway population growth to reduced fertility and mortality and population growth approaching replacement levels. Among the outcomes of fertility decline, 3 have particularly far reaching effects: 1) Changes in family types and structures. Marriage and family formation are postponed, childbearing is compressed into a narrow reproductive span that begins later and ends earlier, and higher-order births become rare. Large families are replaced by small ones, and joint and extended families tend to be replaced by nuclear families. 2) Shifts in the proportions of young and old. Declining fertility means that the population as a whole becomes older. Decreases in the proportion of children provides an opportunity to increase the coverage of education. Increases in the proportion of the elderly means higher medical costs and social and economic problems about care of the aged. 3) Changes in the work force. There is concern that low fertility and shortages of workers will cause investment labor-intensive industries to shift to countries with labor surpluses. Another outcome may be an increase in female participation in the work force. The potential consequences of rapid fertility decline have sparked debate among population experts and policy makers throughout Asia. Current family planning programs will emphasize: 1) offering a choice of methods to fit individual preferences; 2) strengthening programs for sexually active unmarried people; 3) encouraging child spacing and reproductive choice rather than simply limiting the number of births; 4) making information available on the side effects of various family planning methods; 5) providing special information and services to introduce new methods; and 6) promoting the maternal and child health benefits of breast feeding and birth spacing.