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1.
In the early 1950’s, more deaths than births began to occur in a few counties of the United States. The phenomenon has since spread, especially in the 1960’s. In 1966 it occurred in 271 counties, and had affected a total of 324 counties since 1950. Natural decrease had earlier been present in some areas of the United States during the 1930’s. At that time, it was primarily associated with population of low intrinsic fertility. Its occurrence since 1950, however, has not been related to inadequate childbearing rates, but rather to the development of distorted age structures. In most eases, the distortion is the product of prolonged and heavy outmigration of young adults to the extent that the number of couples of childbearing age remaining in an area is insufficient to produce births in excess of the number of deaths occurring to the larger older population. In a minority of cases, the excess of deaths has resulted from large in-migration of older people into retirement areas. The occurrence of natural decrease has been most heavily concentrated in the central part of the country, especially in marginal Corn Belt areas of Missouri, Kansas, Nebraska, and Iowa. It has also been common in central Texas. The counties affected are typically rural and agricultural, with a high median age, a history of population decline, and average population fertility. They had a total 1960 population of 4,003,000 persons. It is projected that an excess of deaths over births will have affected 520 or more counties by 1970, or about a sixth of all counties in the Nation. Given the increasing extent of the condition, research appraising its social and economic consequences for an area is urged.  相似文献   

2.
The substantial growth and geographic dispersion of Hispanics is among the most important demographic trends in recent U.S. demographic history. Our county-level study examines how widespread Hispanic natural increase and net migration has combined with the demographic change among non-Hispanics to produce an increasingly diverse population. This paper uses U.S. Census Bureau data and special tabulations of race/ethnic specific births and deaths from NCHS to highlight the demographic role of Hispanics as an engine of new county population growth and ethnoracial diversity across the U.S. landscape. It highlights key demographic processes—natural increase and net migration—that accounted for 1990–2010 changes in the absolute and relative sizes of the Hispanic and non-Hispanic populations. Hispanics accounted for the majority of all U.S. population growth between 2000 and 2010. Yet, Hispanics represented only 16 % of the U.S. population in 2010. Most previous research has focused on Hispanic immigration; here, we examine how natural increase and net migration among both the Hispanic and non-Hispanic population contribute to the nation’s growing diversity. Indeed, the demographic impact of rapid Hispanic growth has been reinforced by minimal white population growth due to low fertility, fewer women of reproductive age and growing mortality among the aging white population America’s burgeoning Hispanic population has left a large demographic footprint that is magnified by low and declining fertility and increasing mortality among America’s aging non-Hispanic population.  相似文献   

3.
S. Mitra 《Demography》1990,27(1):121-129
The long-term demographic effects of immigration on a population experiencing below-replacement fertility are studied by assuming that the size and age composition of the immigrant population do not change over time. The size of the first-generation immigrant population becomes stationary within a time period not greater than the human life span. Thereafter, the number dying equals the number entering over any given time interval. The stationarity of the native population, among which deaths exceed births, is maintained by the compensating number of births to the immigrant population. The limiting age distribution of the country's population, although stationary, may not decline monotonically with age and may look like a camel's back, with one or two humps.  相似文献   

4.
Focus in this discussion of population trends and dilemmas in the Soviet Union is on demographic problems, data limitations, early population growth, geography and resources, the 15 republics of the Soviet Union and nationalities, agriculture and the economy, population growth over the 1950-1980 period (national trend, regional differences); age and sex composition of the population, fertility trends, nationality differentials in fertility, the reasons for fertility differentials (child care, divorce, abortion and contraception, illegitimacy), labor shortages and military personnel, mortality (mortality trends, life expectancy), reasons for mortality increases, urbanization and emigration, and future population prospects and projections. For mid-1982 the population of the Soviet Union was estimated at 270 million. The country's current rate of natural increase (births minus deaths) is about 0.8% a year, higher than current rates of natural increase in the U.S. (0.7%) and in developed countries as a whole (0.6%). Net immigration plays no part in Soviet population growth, but emigration was noticeable in some years during the 1970s, while remaining insignificant relative to total population size. National population growth has dropped by more than half in the last 2 decades, from 1.8% a year in the 1950s to 0.8% in 1980-1981, due mostly to declining fertility. The national fertility decline masks sharp differences among the 15 republics and even more so among the some 125 nationalities. In 1980, the Russian Republic had an estimated fertility rate of 1.9 births/woman, and the rate was just 2.0 in the other 2 Slavic republics, the Ukraine and Belorussia. In the Central Asian republics the rates ranged up to 5.8. Although the Russians will no doubt continue to be the dominant nationality, low fertility and a relatively higher death rate will reduce their share of the total population by less than half by the end of the century. Soviet leaders have launched a pronatalist policy which they hope will lead to an increase in fertility, at least among the dominant Slavic groups of the multinational country. More than 9 billion rubles (U.S. $12.2 billion) is to be spent over the next 5 years to implement measures aimed at increasing state aid to families with children, to be carried out step by step in different regions of the country. It is this writer's opinion that overall fertility is not likely to increase markedly despite the recent efforts of the central authorities, and the Russian share of the total population will probably continue to drop while that of Central Asian Muslim peoples increases.  相似文献   

5.
Abstract A complete and efficient registration system, of the type which would provide good data on births and deaths, does not exist in Ghana. However, registration of vital events is supposed to be compulsory in 39 towns in the country but the data collected in these areas are too inadequate and defective to provide a sound basis for the analysis of the dynamics of population growth. The results of the censuses conducted by the colonial governments are so defective and unreliable that they do not allow scientific research in the field of population analysis. Before 1960, therefore, when the national census and the post-enumeration survey (based on a 5% sample of the population) were carried out, estimates of fertility and mortality levels were little more than guesses. In this study an attempt has been made to utilize the information on the age-sex composition provided by the 1960 census and post-enumeration survey data on births and deaths to determine, as far as possible, the levels of fertility and mortality and the rates of population growth in Ghana. The fertility estimates-i.e. a crude birth rate of 50, total fertility rate of 6.9 and a gross reproduction rate of 3.4-show that Ghana's fertility is one of the highest in the world. An expectation of life at birth of 40 years, an infant mortality of 160 and a crude death rate of 23 appear to be the most plausible estimates. These estimates yield a rate of natural increase of 2.7% and a growth rate of 3.0% per annum.  相似文献   

6.
Kenya's record population growth: a dilemma of development   总被引:1,自引:0,他引:1  
The causes and implications of Kenya's 4% rate of natural increase and fertility rate of 8.1 births per woman were examined. Attention was directed to the following: pronatalist pressures; inadvertent pronatalist impact of development; women's education and employment and fertility; population growth and pressures; mortality decline and population growth; fertility levels and differentials; fertility desires; the family planning program; and family planning knowledge, attitudes, and practice. Kenya's development success has worked to push up the population growth rate. Improved health care and nutrition halved infant mortality from 160 to 87 deaths/1000 live births between 1958 and 1977 and a marked increase in primary school enrollment may be factors in the birthrate increase to 53/1000 population. At this time fertility is highest among women with 1-4 years of education. The 1977-1978 Kenya Fertility Survey showed that only 5.8% of married women were using modern contraception, indicating that the national family planning program, established in 1967, has made little progress. Program difficulties have included shortages of staff, supplies and easily accessible clinic as well as an almost universal desire on the part of Kenyans for families of at least 7 children. Children are viewed as essential to survival and status to the rural population.  相似文献   

7.
Past efforts of statistical demographers to compute postcensal population estimates for local units have been hampered by the fact that they have had to rely completely on symptomatic information. In this paper, a new method of postcensal estimation is presented in which the symptomatic information is combined with sample data by means of a regression format. Combining symptomatic information on births, deaths, and school enrollment with sample data from the Current Population Survey, county estimates of population growth were computed by means of the new method for the postcensal period after 1960. These estimates were tested for accuracy by comparison with a set of special censuses which were conducted between 1964 and 1967 in 75 counties. The results of this test are promising, but not conclusive. A more conclusive test is currently underway using 1970 data. While the method has been tested as a means for estimating population growth, it is to be emphasized that it can be used to compute postcensal estimates for any variable for which the necessary symptomatic information and sample data are available.  相似文献   

8.
North and South Korea have both experienced demographic transition and fertility and mortality declines. The fertility declines came later in North Korea. In 1990, the population was 43.4 million in South Korea and 21.4 million in North Korea and the age and sex compositions were similar. This evolution of population structure occurred despite differences in political systems and fertility determinants. Differences were in the fertility rate and the rate of natural increase. The total fertility rate was 2.5 children in North Korea and 1.6 in South Korea. The rate of natural increase was 18.5 per 1000 in North Korea and 9.8 in South Korea. Until 1910, the Korean peninsula was in the traditional stage characterized by high fertility and mortality. The early transitional stage came during 1910-45 under the Japanese annexation. Health and medical facilities improved and the crude birth rate rose and then declined. With the exception of the war years, population expanded as a function of births, deaths, and international migration. Poor economic conditions in rural areas acted as a push factor for south-directed migration, migration to Japan, and urban migration. Next came the chaotic stage, during 1945-60. South Korean population expanded during this period of political unrest. Repatriation and refugee migration constituted a large proportion of the population increase. Although the war brought high mortality, new medicine and disease treatment reduced the mortality rate after the war. By 1955-60, the crude death rate was 16.1 per 1000 in South Korea. The crude birth rate remained high at 42 per 1000 between 1950-55. The postwar period was characterized by the baby boom and higher fertility than the pre-war period of 1925-45. Total fertility was 6.3 by 1955-60. The late transitional stage occurred during 1960-85 with reduced fertility and continued mortality decline. By 1980-85, total fertility was 2.3 in the closed population. The restabilization stage occurred during 1985-90, and fertility declined to 1.6. In North Korea, strong population control policies precipitated fertility decline. In South Korea, the determinants were contraception, rising marriage age, and increased use of abortion concomitant with improved socioeconomic conditions.  相似文献   

9.
The population of Henan Province is 72,850,000, 92% of whom live in villages. From July 12 to August 11, 1981, a fertility survey was taken of 20 communes and 31 work brigades in the counties of Fugou, Shancai, and Dengfeng, in which 38,168 people and 5700 fertility registration forms were studied. In 1980, 15% of the 3 counties' population were women aged 18-49, 80% of whom were married. The birth rate was 134.56/1000, of which the rate for married women was 172.36/1000. A random sampling from Shancai of 18-49 year old women showed an average of 2.3 children per couple. The factors influencing rural fertility are economic, social, ideological, and cultural. The economic system of distribution according to work has actually encouraged population growth because in rural areas where the standard of living is low larger families with more workers have greater incomes than smaller families with fewer workers. Early marriage and early births are encouraged under this system, as evidenced by findings in Fugou County. The survey also found that in the 3 counties, virtually everyone marries, women who work tend to work in the village close to home, high illiteracy is prevalent, and traditional attitudes of favoring males over females were all factors contributing to early and frequent births. In order to lower rural birth rates, rural economy should be developed, old attitudes and habits should be changed, and literacy should be increased.  相似文献   

10.
This article examines the prevalence and dynamics of natural decrease in the subnational populations of Europe and the United States. Natural decrease results from interactions between fertility, mortality, and migration over a protracted period. We document the greater incidence and degree of natural decrease in Europe. In the first decade of the twenty‐first century, natural decrease occurred in 58 percent of European NUTS 3 areas (“counties”) compared to only 28 percent of the US counties. Three critical demographic variables (proportion over 65, child‐women ratio, and proportion of women of childbearing age) each exert a significant and distinct impact on the likelihood of natural decrease. Our spatial regression models reflect remarkable consistency in the influence of each of these variables in Europe and in the US, demonstrating the similarity in the demographic processes that produce natural decrease.  相似文献   

11.
Projections of total population have been evaluated extensively, but few studies have investigated the performance of projections by age. Of those that did, most focused on projections for countries or other large areas. In this article, we evaluate projections by age for Florida and its counties, as produced and published between 1996 and 2010 by the Bureau of Economic and Business Research at the University of Florida. We first compare the precision and bias of projections of total population with the precision and bias of projections by age, at both the state and county levels. This is followed by a more detailed examination of county-level projection errors for individual age groups, first in the aggregate and then disaggregated by sex and population size. The second part of the analysis focuses on a number of adjustments that were implemented in projections published in 2006 and 2009. Intended to improve accuracy, these adjustments involved updates to the base population, fertility rates, and survival rates. We compare the accuracy of projections incorporating these adjustments with the accuracy of projections excluding them. We believe this study offers a unique opportunity to examine a variety of characteristics regarding the forecast accuracy of small-area population projections by age.  相似文献   

12.
All states will have more people in the future, especially in the south and west, while population aging occurs as the baby boomers age. This report identifies population changes projected to affect the US's 50 states and District of Columbia during 1995-2015. Basic assumptions for state population projections are presented with regard to population, births, deaths, net international migration, and net internal migration. The methodology used to produce the report is also described. Total population and net change is presented in tabular format for each state over the period. These data are used as the basic input to many federal, state, and local projection models which produce detailed statistics on education, economic factors, labor force, health care, voting, and other subjects. State differentials in fertility and mortality are also projected to widen, reflecting the concentration of race and ethnic groups with high fertility in some states and differential migration patterns.  相似文献   

13.
New estimates of intergenerational economic mobility reveal substantial variation in the spatial distribution of opportunity in the United States. Efforts to explain this variation in economic mobility have conspicuously omitted health despite it being a key pathway for the transmission of economic position across generations. We begin to fill this gap in the literature by examining the relationship between health endowment at birth and intergenerational economic mobility across county birth cohorts in the United States, drawing on estimates from two population-level data sets. Exploiting variation across counties and over time, we find a negative relationship between the incidence of low-weight births and the level of economic mobility as measured in adulthood for the county birth cohorts in our sample. Our results build on a large and growing literature detailing the role of early childhood health in the transmission of economic status across generations and suggest that the incidence of low-weight births is negatively associated with intergenerational economic mobility.  相似文献   

14.
Europe's second demographic transition   总被引:2,自引:0,他引:2  
By 1985, fertility rates in Europe were below the replacement level of 2.1 births/woman in all but Albania, Ireland, Malta, Poland, and Turkey, following a steady decline from a 1965 postwar peak well above 2.5 in Northern, Western, and Southern Europe and an erratic trend from a lower level in Eastern Europe. Natural decrease (fewer births than deaths) had begun already in Austria, Denmark, Hungary, and the Federal Republic of Germany and can be expected shortly in many other countries. According to current UN medium projections, Europe's population (minus the USSR) will grow only 6% between 1985 and 2025, from 492 to 524 million and 18.4% of the population in 2025 will be 65 and over. The decline to low fertility in the 1930s during Europe's 1st demographic transition was propelled by a concern for family and offspring. Behind the 2nd transition is a dramatic shift in norms toward progressiveness and individualism, which is moving Europeans away from marriage and parenthood. Cohabitation and out-of-wedlock fertility are increasingly acceptable; having a child is more and more a deliberate choice made to achieve greater self-fulfillment. Many Europeans view population decline and aging as threats to national influence and the welfare state. However, governments outside Eastern Europe, except for France, have hesitated to try politically risky and costly economic pronatalist incentives. As used in Eastern Europe, coupled with some restrictions on legal abortion, such incentives have not managed to boost fertility back up to replacement level. Immigration as a solution is unfeasible. All countries of immigration have now imposed strict controls, tried to stimulate return migration of guestworkers recruited during labor shortages of the 1960s and early 1970s, and now aim at rapid integration of minorities. Only measures compatible with the shift to individualism might slow or reverse the fertility decline, but a rebound to replacement level seems unlikely and long-term population decline appears inevitable for most of Europe.  相似文献   

15.
Our analysis of changing birth interval distributions over the course of a fertility transition from natural to controlled fertility has examined three closely related propositions. First, within both natural fertility populations (identified at the aggregate level) and cohorts following the onset of fertility limitation, we hypothesized that substantial groups of women with long birth intervals across the individually specified childbearing careers could be identified. That is, even during periods when fertility behavior at the aggregate level is consistent with a natural fertility regime, birth intervals at all parities are inversely related to completed family size. Our tabular analysis enables us to conclude that birth spacing patterns are parity dependent; there is stability in CEB-parity specific mean and birth interval variance over the entire transition. Our evidence does not suggest that the early group of women limiting and spacing births was marked by infecundity. Secondly, the transition appears to be associated with an increasingly larger proportion of women shifting to the same spacing schedules associated with smaller families in earlier cohorts. Thirdly, variations in birth spacing by age of marriage indicate that changes in birth intervals over time are at least indirectly associated with age of marriage, indicating an additional compositional effect. The evidence we have presented on spacing behavior does not negate the argument that parity-dependent stopping behavior was a powerful factor in the fertility transition. Our data also provide evidence of attempts to truncate childbearing. Specifically, the smaller the completed family size, the longer the ultimate birth interval; and ultimate birth intervals increase across cohorts controlling CEB and parity. But spacing appears to represent an additional strategy of fertility limitation. Thus, it may be necessary to distinguish spacing and stopping behavior if one wishes to clarify behavioral patterns within a population (Edlefsen, 1981; Friedlander et al., 1980; Rodriguez and Hobcraft, 1980). Because fertility transition theories imply increased attempts to limit family sizes, it is important to examine differential behavior within subgroups achieving different family sizes. It is this level of analysis which we have attempted to achieve in utilizing parity-specific birth intervals controlled by children ever born.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

16.
Traditional family planning's emphasis on manipulating the total fertility rate often results in erratic number of births which disrupts school enrollment and labor supply. Fixing total annual births to a permanently lower level will avoid such repeated disruptions and can eventually lead to a lower stationary population with annual deaths equal to the fixed annual births. If allocation of the fixed birth quotas is conditional upon deaths, each death can be converted to a variable number of inheritable and tradable birth quotas. Tradable birth coupons allow families to have the number of children they want and can afford within the overall fixed birth quotas. Inheritable birth quotas provide incentive for higher old-age mortality and consequently less aging in a declining population.  相似文献   

17.
张建武  李楠  赵勋 《南方人口》2011,26(6):56-62
大量研究证实流动人口会降低全国各城市生育率水平,但是两者的数量关系仍然不是十分清楚。本文以广东为例,利用1990—2005年广东流动人口和出生人口数据,对流动人口变动与广东出生人口数量关系进行了实证研究。  相似文献   

18.
Simple probability models incorporating an approximation first demonstrated by Menken (1979) are used to study births averted by two classes of temporary spouse separation, single and cyclic, under conditions of natural fertility. For either class of spouse separation, births averted increases disproportionately with longer separation. For a given length of separation, births prevented are more sensitive to change in length of anovulation than to change in level ofnatural fecundability or risk of spontaneous abortion. In addition, by means of the macrosimulation model REPMOD (Bongaarts, 1977), it is shown that the fertility impact of temporary spouse separation tends to decrease as couples age.  相似文献   

19.
This discussion of the population of China covers the reproductive pattern and fertility rate, the death pattern and mortality, age-sex structure of the population, population and employment, urbanization, migration, and the aging of the population. During the 1949-83 period, China almost doubled her population with an annual natural growth rate of 19/1000. China's reproductive pattern developed from early childbearing, short birth spacing and many births to later childbearing, longer birth spacing and fewer births. China's total fertility rate (TFR) was 5.8 in 1950 and 2.1 in 1983 with an annual decrease of 3%. The annual national income grew at a rate of 7.1%, while the annual growth rate of population 1.9% from 1950-82. Consequently, the national income per capita increased from 50 yuan in 1950 to 338 yuan in 1982. The major factor responsible for the changes is the remarkable decline in the rural fertility rate. The crude death rate dropped from 27.1/1000 in 1963 to 7.1 in 1983 and the infant mortality rate from 179.4/1000 live births in 1936 to 36.6 in 1981. There was also a significant change in the causes of death. Population aged 0-14 in China account for 33.6%, 15-49 for 51.3%, and 50 and over for 15.1% of the total population. China is in the process of transition from an expansive to a stationary population. The age-dependency ratio declined from 68.6% in 1953 and 79.4% in 1964 to 62.6% in 1982. Sex ratios recorded in the 3 population censuses are 105.99 in 1953, 105.45 in 1964, and 105.46 in 1982. Employment in both collective and individual economies did not expand until 1978. Sectoral, occupational, and industrial structures of population started to change rationally with the adjustment and reform of economic management system in 1978. The strategic stress on the employment of China's economically active population should be shifted from farming to diversified economy and urban industry and commerce, from sectors of industrial-agricultural production to those of non-material production, and from expansion of employment to the rise of employment efficiency. The proportion of urban population in China accounted for 20.8% in 1982 with an annual growth rate of 4% during the 1949-82 period. The 1982 population census reveals that 94.4% of China's population resides on the southeast side of Aihui-Tengchong Line. Compared with the statistics in 1953, there was no notable change of the unbalanced population distribution on each side of the Line over the last 50 years. China is comparatively young in its population age structure. 1982 census data show that there were 49.29 million people at age 65 and over in 1982, representing 4.91% of the whole population. It is estimated from the age composition of 1982 and age-specific mortality rate of 1981 that there will be 88 million elderly persons by 2000, 150 million by 2020, and about 300 million as a maximum around 2040.  相似文献   

20.
"In this paper, we consider crossovers of demographic density distributions from...populations that have the same fertility and mortality rates. We focus on observed populations and their associated stationary and stable models, and on proportional distributions of persons, births, deaths and reproductive values....Three different populations were selected to represent a range of demographic behavior. Those populations are Japan 1963, a low mortality, low fertility population; Togo 1961, a high mortality, high fertility population; and the United States 1919-1921, a population whose fertility and mortality are intermediate."  相似文献   

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