A decomposition of trends in the nonmarital fertility ratios of blacks and whites in the united states, 1960–1992*

We use a method of standardization and decomposition developed by Das Gupta to update Smith and Cutright’s analysis of demographic factors responsible for increases in the nonmarital fertility ratio (illegitimacy ratio) among blacks and whites in the United States. We create standardized rates for each year between 1960 and 1992, and consistent, exhaustive decompositions of the nonmarital fertility ratio for any interval during this period in terms of four components: (1) the age distribution of women of reproductive age, (2) the proportion of women unmarried at each age, (3) the age-specific birth rates of married women, and (4) the age-specific birth rates of unmarried women. Nonmarital fertility ratios are much higher among blacks than among whites, but both increased monotonically from 1960 to 1992. During the last 10 years, each increased by nearly 10 percentage points. Increases in the proportion of women not married, at all ages, account for the preponderance of the increase in black nonmarital fertility ratios. Increasing rates of unmarried childbearing, however, have played a role during the most recent decade (1983–1992). For whites, from 1960 until 1975, declines in marital fertility were most important in producing increases in the proportion of children born out of wedlock. Since then, these proportions have increased primarily because of increases in unmarried women s birth rates, and secondarily because of declines in the proportion of women who are married. These trends are consistent with arguments that emphasize declining economic incentives to marry and reduced access to, and acceptability of, abortion.     

Sex preference versus number preference: the case of Korea

The author argues that the effect of sex preference must be disentangled from the effect of number preference in Korea. This study tests--with hazard models--the effect of the number of previous children on the next birth according to the sex composition of previous children. Data were obtained from the 1974 Korean Fertility Survey. This paper also analyzes the timing of childbearing in recent periods in order to determine whether replacement-level fertility is temporary or permanent. The ideal number of children declined from 3.9 children in 1965 to 2.1 in 1991. The age-specific fertility rates for ages 20-24 years declined rapidly during the late 1980s. The fertility rates among women aged 25-29 years and 30-34 years increased during 1985-90. The proportion of fertility among women aged 20-29 years increased from 67.9% in 1975 to 86.6% in 1984. Women born in the late baby boom period of the late 1950s to mid-1960s reached prime reproductive age during the late 1980s and 1990s, but the crude birth rate remained about the same during 1985-92. A higher percentage of women (22.4%) born during 1955-59 remained single in 1990. During 1960-90, the percentage of women aged 20-24 years who were married declined. These trends indicate later age at childbearing and an explanation for the temporary nature of below-replacement fertility in the late 1980s. Korean women did not want to have more than 2 children, and the interval between first and second births increased since 1985. Among pregnancies of parity 2 conceived since 1985, over 90% of women with at least one son ended subsequent pregnancies by abortion compared to only 59% without sons. Hazard models of 1974 data reveal that son preference had an important effect on fertility. Fertility was higher among women with only daughters. Findings suggest that the value of sons must be measured at the societal and not at the individual level.     

Fertility and economic activity of women in Guatemala city, 1964

Data from a five percent census sample reveal that in Guatemala City in 1964 economically active women, especially domestic servants, had lower cumulative fertility than inactive women, partly because larger proportions of them had never married and were childless. However, even among ever married mothers there was a substantial differential, which was not due to differences in age at first birth. With respect to all women, cross tabulation and regression analysis show that age, marital status and educational attainment were more strongly associated with fertility than was activity status, but the latter also had a significant net association. Selection for sterility was not likely. Being contrary to expectations expressed in the literature, the very low fertility of the domestics received further attention. Live-in domestics had considerably lower fertility than those who lived out, which was also the case in the United States in 1960. These data and other evidence strongly suggest that this differential is due to a widespread employer preference for single or childless women. The concept of role incompatibility is therefore inapplicable to domestic servants. These findings add to the considerable evidence showing lower fertility among economically active women in large urban places in Latin America.     

Constructing fertility tables for Soviet populations

Because the 1970 Soviet Union census does not provide information on the age structure of men and women separately by sex and according to their ethnic affiliation, the 1959 USSR census data serve as the basis to infer knowledge about ethnic fertility. The model takes into account (1) the total number of births in 1960, estimated from the child-woman ratio in 1959, (2) the age structure of women in 1959, and (3) the assumed pattern of age-specific birth rates structured in terms of the modal age at childbearing and the length of the fertility age span. The results show that Ukrainians among the Slav populations ranked as the lowest with 2.07 children born per woman. Their total fertility contrasts with that of Kazakhs native to Central Asia, who reportedly according to Soviet sources had 7.46 children per woman in 1958-1959, and whose estimated rate is around 8.59 children. Extreme variations appear in the estimates of fertility among nationalities of the Caucasus region, Volga Basin, and to a lesser degree in Siberia. Official Soviet calculations of crude birth rates and age-specific rates for 15 Union Republics in 1967-1968 are transcribed and compared with the estimates for nationalities in 1959-1960. The same theoretical model used to generate the Soviet rates may be adapted under different assumptions to non-Soviet populations in other situations where the data are scanty or incomplete.     

Age-parity-specific birth rates and birth probabilities from census or survey data on own children

The ‘own-children’ method is a census- or survey-based reverse-survival technique for estimating age-specific birth rates for years previous to enumeration. In this paper it is extended to estimate birth rates and birth probabilities by parity as well as by age. The refined method is tested for accuracy by comparing ‘own-children’ estimates of age-parity-specific birth probabilities for the United States in 1969 with parallel estimates obtained by the method used in Vital Statistics of the United States. The ‘own-children’ estimates give relatively lower values at ages 15-19 and higher values at ages above 40, but compare well in between. The discrepancies are probably due mainly to adoption of illegitimate children of young mothers by older women. The ‘own-children’ estimate of the total fertility rate is very close to the published vital statistics estimate.     

Distinctive features of age-specific fertility profiles in the English-speaking world: common patterns in Australia,Canada, New Zealand and the United States, 1970-98

The paper seeks to identify common features in the fertility patterns of the English-speaking world and provide a model basis for comparison of fertility between countries and over time. Attention is focused on the heterogeneity within the fertility patterns of Australia, Canada, New Zealand, and the United States, similar to that reported earlier for the UK and the Irish Republic. The recent age-specific fertility patterns of these countries display a marked 'bulge' in fertility of women under age 25. A mixture model with two-component Hadwiger functions provides a suitable fit. The heterogeneity thus suggested is related to the proportion of births outside marriage. Additionally, there is some evidence that, in the United States, and lesser extent in New Zealand, this heterogeneity in fertility patterns may be explained by ethnic difference in the timing and number of births.     

Statistical modeling of selected aspects of the childbearing process with application to World Fertility Survey countries

"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 [World Fertility Surveys conducted in developing] 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." (SUMMARY IN FRE)     

An analysis of the fertility of Chinese women]

The 1982 census provided detailed information on fertility in China. It recorded 20,689,704 births in 1981, producing a birth rate of 2.1%, a decrease, respectively, of 43% and more than 50% in comparison with 1952 and 1963. The birth rate has varied widely over the last 30 years, from 3.6% in the early 1950's, to 1.8% in 1961, after a planned birth program was begun, to a record high of 3.7% in 1962 following the economic recovery, to 3.3% in 1970, after a gradual decline through the 1960's. By 1981 the birth rate had declined to 2.1%, clearly resulting from the intense planned fertility promotion begun in the early 1970's. In the mid- and late 50's, urban birth rate was consistently higher than rural, with the mass move to the cities at the beginning of the People's Republic. General economic development after 1957 brought simultaneous declines of both urban and rural rates, both reaching a low point in 1961. Age structure of the population also has an influence, depending on the proportion of childbearing women in the population. In 1981, the fertility of China's childbearing women was 8.3%, lower than that of the developing countries, but higher than the developed countries. By age group, the fertility rates reached 14.7% and 23.9% respectively in women between 20-24 and 25-29 years of age; the legal marriage age is 20. The fertility rate in large cities is generally lower than that of provinces. Higher educational and socio-economic level also exert an inverse influence on fertility rates; in low socio-economic areas the rate reached 3.5%, and in more advanced areas it was held to 2.2%. In all professions with the exception of agriculture, fishing, and forestry, the percentage of families with 1 child was 81.8%. Since planned fertility was implemented, the overall fertility rate has dropped from 3% to 2%. China's fertility mode has changed to that of developed countries, with high intensity between 20 and 29 years of age. Appropriate measures should be taken to lower the fertility rate in different regions.     

Reproductive ideals and educational attainment among white Americans, 1943-1960

Abstract Would the persistent inverse relation between educational attainment and family size in the United States be removed if actual fertility were equal to ideal? Data on ideal family size from 10 national surveys among white Americans of both sexes (from 1943 to 1960) show that gradeschool level respondents have higher ideals than the more educated even when age, religious affiliation, and farm residence are used as controls. Comparison of these ideals with the actual family size or ever-fertile women in the United States indicates that, on the average, the actual family size of all major educational groups falls below the ideal, but the college-educated are furthest from their ideal. If this group lessened the gap between actual and ideal family size, the educational differential in fertility would decrease, but at the price of increasing the rate of population growth.     

Changes in childlessness in the United States: A demographic path analysis

Summary This paper describes changes in the incidence of marital childlessness among United States women since 1940 and tests a model to explain recent observed trends toward increasing childlessness. Based on U.S. Bureau of the Census sources, data are presented that indicate a substantial increase in childlessness for married women under 30 years of age since 1960. A path model is developed based on previous research on childlessness, in an attempt to explain this change. The model is composed of 1960-70 changes in (1) mean age at first marriage, (2) mean educational attainment, (3) the proportion of women in the labour force, (4) the proportion of women enrolled as students, (5) the incidence of marital disruption, and (6) the proportion of women living in urban environments. Using quarter-year age cohort data derived from the 1960 and 1970 1/100 Public Use Samples the results indicate that a substantial part of the increase in childlessness csn be explained by this model. Particularly important were increased enrolment of married women in education, labour force participation, and mean age of first marriage. The results suggest the relevance of structural changes along with birth expectation attitudes in predicting trends in childlessness in the United States.     

Impact of population changes on education cost

This paper has two principal aims: (1) to analyze and measure how the demographic variables—mortality, fertility, and im migration — affect the cost of education; (2) to evaluate what possibilities developing countries, such as those of Latin America, have for a rapid educational improvement. The paper relates demographic and educational variables of three different populations: Sweden, 1840–1965; the United States, 1850–1960; and Latin America, 1930–2000. Three educational variables are also considered: (a) school attendance rates by sex and age; (b) distribution of students of same age by grade; and (c) cost of student by grade. Demographic changes in countries such as Sweden and the United States were favorable for the development of education. For the future, unless an increase of fertility occurs, mortality and fertility changes will not have a significant effect on the cost of education in these countries. In current less developed countries the demographic changes during the past were less favorable to educational development. A future reduction of fertility will significantly help them to achieve a higher educational level.     

A new method for estimating the level of natural fertility in populations practicing birth control

The natural fertility schedule of a population is the schedule of age-specific marital fertility we would observe if no birth control were being practiced. In natural fertility (no birth control) populations we can observe the natural fertility schedule directly, but in populations practicing birth control the natural fertility schedule is disguised by the marital fertility rates in those age intervals in which control is exercised, the marital fertility rates being below the natural rates. This paper elaborates a method for estimating the natural fertility schedules of populations practicing birth control. Two alternative models are presented, one nonlinear and one linear. The use of these models is then illustrated with reference to the Old Order Amish population of Lancaster County, Pennsylvania. It is shown that for Amish women born between 1860 and 1900 both the nonlinear and linear models yield an estimate of .843 as the ratio between Amish and Hutterite natural fertility schedules.     

Maybe Next Month? Temperature Shocks and Dynamic Adjustments in Birth Rates

We estimate the effects of temperature shocks on birth rates in the United States between 1931 and 2010. We find that days with a mean temperature above 80°F cause a large decline in birth rates 8 to 10 months later. Unlike prior studies, we demonstrate that the initial decline is followed by a partial rebound in births over the next few months, implying that populations mitigate some of the fertility cost by shifting conception month. This shift helps explain the observed peak in late-summer births in the United States. We also present new evidence that hot weather most likely harms fertility via reproductive health as opposed to sexual activity. Historical evidence suggests that air conditioning could be used to substantially offset the fertility costs of high temperatures.     

Fertility of the american negro in 1830 and 1850

Abstract A comparison of the proportionate age distributions for negroes enumerated in the decennial censuses of the United States in the first half of the rorh century indicates that by 1850, negro fertility apparently had been declining for at least 20 years. This paper develops the relationship of the age distribution of a declining fertility population, where the decline has persisted for less than 25 years, to the stable population with the same current schedules of fertility and mortality. This relationship is used to estimate the negro birth rate and total fertility as of 1850. In turn, these estimates and the relationship of the age distributions of two stable populations with different fertility are used to estimate the negro birth rate and total fertility as of 1830.     

Family planning achievements as suggested by changes of total fertility and party birth rate]

The dynamic characteristics of China's 5 distinct stages of population development since the People's Republic of China was established in 1949, namely, 1950-1958, 1959-1963, 1964-1970, 1971-1981, and 1982-present, are outlined and discussed. By tracing both the overall rate of population growth and age-specific fertility rates for women aged 15-45 (5-year groups), a clear pattern emerges which indicates that the rates of early and late fertility (ages groups 15-19 and 30-45) are significantly declining. This is interpreted as a key factor in the overall decline in fertility rate. Annual statistics showing the number of children per woman of childbearing age and interval between 1st marriage and 1st birth are compared and discussed. It is concluded that the overall decline in birth rate and fertility rate since the 1970's is attributable to China's successful family planning campaign.     

Intergenerational Transmission of Age at First Birth in the United States: Evidence from Multiple Surveys

It is well established that the timing of childbearing is transmitted from parents to children in the United States. However, little is known about how the intergenerational link has changed over time and under structural and ideological transformations associated with fertility behaviors. This study first considers changes across two birth cohorts from the National Longitudinal Survey of Youth (NLSY) in the extent to which parents’ age at first birth is transmitted to their children. The first cohort includes individuals born during the late 1950s through the early 1960s (NLSY79), while the second includes individuals born in the early 1980s (NLSY97). Results from discrete-time event history analyses indicate that the intergenerational transmission of age at first birth significantly increased for both daughters and sons. These results were confirmed by analyses of data from three cycles of the National Survey of Family Growth spanning the same time period. Over this period, age at first childbirth became increasingly younger for children born to teenage mothers and increasingly older for those born to mothers who began parenthood after age 25. These patterns have important implications for the reproductive polarization hypothesis.     

What’s happening to the age at first birth in the United States? A study of recent cohorts

This paper analyzes cross-cohort trends in the age pattern of women at first birth in the United States. The analysis involves fitting the Coale-McNeil marriage model to the age distribution of first birth frequencies for a number of recent white and nonwhite cohorts. Methodologically, the results (a) provide support for the application of the Coale-McNeil marriage model to first birth data, and (b) demonstrate the ability of the model to accurately project first birth fertility for cohorts which have yet to complete their childbearing years. Substantively the results indicate (a) that the proportion of women who will never have a first birth is increasing across cohorts and can be expected to be as high as .25 and .20 for recent white and nonwhite cohorts respectively; (b) that recent nonwhite cohorts have an appreciable number of first births at earlier ages than their white counterparts, as well as a lower mean age at first birth and increasingly less dispersion (across cohorts) in their age at first birth; and (c) that the mean age at first birth and the proportion of first births occurring between ages 25 and 34 is increasing across cohorts of white women but is stable across cohorts of nonwhite women.     

Regional—sub-cultural explanations of black fertility in the United States

This paper re-examines the relevance of the hypothesis concerning the Southern sub-culture and black fertility in the United States. According to zero-order correlation analysis, Southern-born blacks show higher fertility than those born in other regions. But a dummy-variable regression technique applied to the data from the 1970 public-use sample indicates that the Southern origin — independent of other factors-is not different from other regions. Southern birth has the effect of increasing black fertility, but much less so than birth in the North Central region. Southern blacks show higher fertility because of their lower socio-economic background. It is concluded that geographical regions in the United States have little or no cultural meaning in explaining reproductive behaviour.     

Contraceptive practice required to meet a prescribed crude birth rate target: a proposed macro-model (tabrap) and hypothetical illustrations

TABRAP (TArget Birth Rate Acceptor Program) is a computer programmed model that provides a direct solution to the problem of determining the total annual numbers of contraceptive acceptors required to achieve a prescribed crude birth rate target path. Applied to an initial population for which age structure, the fertility schedule, and expected trends in life expectancy and age-specific proportions of females married are known, TABRAP incorporates the following factors: age at acceptance, with acceptors drawn from currently married nonusers; age-method-specific attrition rates of users; a potential fertility schedule of acceptors that allows for aging and sterility; and allowance both for postpartum anovulation and nine months for gestation to time properly the averted births. TABRAP generates annual data on acceptors, couple-years of use, births averted and age-specific fertility rates that meet the crude birth rate target. Resulting changes in population size, age structure and crude vital rates, also yielded, are invariant with respect to acceptor age and method mix. Assuming a target to reduce the crude birth rate from 45 to 30 in ten years, TABRAP is illustrated for seven mixes of acceptor age-method combinations applied to a population approximately that of Thailand, circa 1965.     

Does It Matter What She Wants? The Role of Individual Preferences Against Unmarried Motherhood in Young Women’s Likelihood of a Nonmarital First Birth

Most young people in the United States express the desire to marry. Norms at all socioeconomic levels posit marriage as the optimal context for childbearing. At the same time, nonmarital fertility accounts for approximately 40 % of U.S. births, experienced disproportionately by women with educational attainment less than a bachelor’s degree. Research has shown that women’s intentions for the number and timing of children and couples’ intent to marry are strong predictors of realized fertility and marriage. The present study investigates whether U.S. young women’s preferences about nonmarital fertility, as stated before childbearing begins, predict their likelihood of having a nonmarital first birth. I track marriage and fertility histories through ages 24–30 of women asked at ages 11–16 whether they would consider unmarried childbearing. One-quarter of women who responded “no” in fact had a nonmarital birth by age 24–30. The ability of women and their partners to access material resources in adulthood were, as expected, the strongest predictors of the likelihood of nonmarital childbearing. Nonetheless, I find that women who said they would not consider nonmarital childbearing had substantially higher hazards of fertility postponement and especially of marital fertility, even after controlling for race/ethnicity, mother’s educational attainment, family of origin intactness, self-efficacy and planning ability, perceived future prospects, and markers of own educational attainment and work experience into early adulthood.