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1.
This study examines population flows from Sydney and other regions to perimetropolitan and coastal areas of New South Wales, the two main foci of the population turnaround since 1971. It uses census internal migration statistics for the five intercensal periods between 1971 and 1996, and estimated resident population statistics between 1997 and 2000. Fluctuating trends are described with respect to variations in age structures of migration flows and net migration gains by SLAs in coastal areas over time. Evidence of fluctuating trends is evaluated in relation to population structure change and local socio-economic multipliers in turnaround areas. The turnaround is far mor than a net migration gain from large metropolitan areas; it is also associated with interregional migration which avoids metropolitan areas, and which is at least in part environment- and amenity-related. The experience of some other countries, such as the USA where net migration reversals in population turn-around regions have occurred, has not been replicated in Australia. While elements of explanation for the complex cumulative causation process of the population turnaround in Australia are discussed, including the issues of fluctuating or cyclical trends, much more understanding of the economic and social factors involved is required.  相似文献   

2.
Aboriginal migration to the cities   总被引:1,自引:1,他引:1  
Aboriginal migration to the cities is frequently assumed to be adding to the population of urban Aborigines. An analysis of actual patterns of Aboriginal migration to the large Australian cities (major urban areas), using data from the 1981 and 1986 Australian Censuses, shows that the major urban areas of New South Wales and Victoria were actually losing Aboriginal population through net migration throughout the period 1976 to 1986. At both inter-State level and country-to-city lev/el, any Aboriginal migration flow in one direction tends to be almost cancelled out by a flow of similar size in the opposite direction. However, there are definite age-specific patterns. In particular, there is movement of young single adults to the cities, often counterbalanced by migration of somewhat older adults with their children to the country. Aboriginal migrants have higher levels of labour-force participation than equivalent categories of non-migrants.  相似文献   

3.
Data on family size by year of marriage, age at marriage, and duration of marriage, from the 1911 Fertility Census, are compared between Scotland, England and Wales, Irish county boroughs, and the rest of Ireland. While means show significant inter-country differences, from the 1880s marked similarities are found across all the countries in the pattern of fertility decline, strongly suggesting significant fertility limitation in rural Ireland well before 1911. Noting the implications for the use of rural Ireland as a natural fertility population, the data are instead compared with the Coale-Trussell and Hinde-Woods schedules. The former provides more plausible results, which imply strong period rather than cohort effects in the fertility decline. Except in rural Ireland, little evidence is found for significant fertility limitation early in marriage among younger marrying couples, but many older marrying couples appear to have stopped childbearing at very low parities from an early date.  相似文献   

4.
The most salient demographic trend pictured by the influential set of population projections prepared by the Population Division of the United Nations (a unit in the UN's Department of Economic and Social Affairs) is the continuing substantial increase—albeit at a declining rate—of the global population during the coming decades. According to the “medium” variant of the most recent (1998) revision of these projections, between 2000 and 2050 the expected net addition to the size of the world population will be some 2.85 billion, a figure larger than that of the total world population as recently as the mid‐1950s. All of this increase will occur in the countries currently classified as less developed; in fact, as a result of their anticipated persistent below‐replacement levels of fertility, the more developed regions as a whole would experience declining population size beginning about 2020, and would register a net population loss of some 33 million between 2000 and 2050. A report prepared by the UN Population Division and released on 21 March 2000 addresses some of the implications of the changes in population size and age structure that low‐fertility countries will be likely to experience. The 143‐page report, issued under the eyecatching title Replacement Migration: Is It a Solution to Declining and Ageing Populations?, highlights the expected magnitude of these changes by the imaginative device of answering three hypothetical questions. The answer to each of these questions is predicated on the assumption that some specified demographic feature of various country or regional populations would be maintained at the highest level that feature would exhibit, in the absence of international migration, in the United Nations' medium population projections (as revised in 1998) during the period 1995–2050. The selected demographic features are total population size, the size of the working‐age population (15–64 years), and the so‐called potential support ratio: the ratio of the working‐age population to the old‐age population (65 years and older). The illustrative device chosen for accomplishing the specified feats of preserving the selected demographic parameters (i.e., keeping them unchanged up to 2050 once their highest value is attained) is international migration. Hence the term “replacement migration.” Given the low levels of fertility and mortality now prevailing in the more developed world (and specifically in the eight countries and the two overlapping regions for which the numerical answers to the above questions are presented in the report), and given the expected future evolution of fertility and mortality incorporated in the UN population projections, the results are predictably startling. The magnitudes of the requisite compensatory migration streams tend to be huge relative both to current net inmigration flows and to the size of the receiving populations; least so in the case of the migration needed to maintain total population size and most so in the case of migration needed to counterbalance population aging by maintaining the support ratio. Reflecting its relatively high fertility and its past and current record of receiving a large influx of international migrants, the United States is a partial exception to this rule. But even for the US to maintain the support ratio at its highest—year 1995—level of 5.21 would require increasing net inmigration more than tenfold. The country, the report states, would have to receive 593 million immigrants between 1995 and 2050, or a yearly average of 10.8 million. The extreme case is the Republic of Korea, where the exercise calls for maintaining a support ratio of 12.6. To satisfy this requirement, Korea, with a current population of some 47 million, would need 5.1 billion immigrants between 1995 and 2050, or an average of 94 million immigrants per year. (In the calculations, the age and sex distribution of migrants is assumed to be the same as that observed in the past in the main immigration countries. The fertility and mortality of immigrants are assumed to be identical with those of the receiving population.) The “Executive Summary” of the report is reproduced below, with the permission of the United Nations. Chapters of the full report set out the issues that prompted the exercise; provide a selective review of the literature; explain the methodology and the assumptions underlying the calculations; and present the detailed results for the eight countries and two regions selected for illustrative purposes. A brief discussion of the implications of the findings concludes the report. As is evident even from the figures just cited, immigration is shown to be at best a modest potential palliative to whatever problems declining population size and population aging are likely to pose to low‐fertility countries. The calculations, however, vividly illustrate that demographic changes will profoundly affect society and the economy, and will require adjustments that remain inadequately appreciated and assessed. The criteria specified in the UN calculations—maintenance of particular demographic parameters at a peak value—of course do not necessarily have special normative significance. Past demographic changes, with respect notably to the age distribution as well as population size, have been substantial, yet they have been successfully accommodated under circumstances of growing prosperity in many countries. But the past may be an imperfect guide in confronting the evolving dynamics of low‐fertility populations. As the report convincingly states, the new demographic challenges will require comprehensive reassessments of many established economic and social policies and programs.  相似文献   

5.
Alho JM 《Demography》2008,45(3):641-650
Fertility is below replacement level in all European countries, and population growth is expected to decline in the coming decades. Increasing life expectancy will accentuate concomitant aging of the population. Migration has been seen as a possible means to decelerate aging. In this article, I introduce a stable, open-population model in which cohort net migration is proportional to births. In this case, the migration-fertility trade-off can be studied with particular ease. I show that although migration can increase the growth rate, which tends to make the age distribution younger, it also has an opposite effect because of its typical age pattern. I capture the effect of the age pattern of net migration in a migration-survivor function. The effect of net migration on growth is quantified with data from 17 European countries. I show that some countries already have a level of migration that will lead to stationarity. For other countries with asymptotically declining population, migration still provides opportunities for slowing down aging of the population as a whole.  相似文献   

6.
During the past quarter century fertility has dropped below replacement levels in many parts of the world. According to United Nations estimates, in 2005 this was the case in 65 countries, comprising 43 percent of the world's population. In many cases, most notably in Europe and East Asia, the shortfall of fertility from the level that would be necessary in the long run to sustain a stationary population is substantial. In Europe, for example, the average total fertility rate for the period 2000–2005 was 1.4. Indefinite maintenance of such a level implies a shrinkage of the total population by one‐third over a generation–roughly every 30 years. Accompanying that rapid decline of total numbers would be an age structure containing a preponderance of the elderly, posing extreme adjustment difficulties for the economic and social system. Societies that wish to avoid radical depopulation would have to engineer a substantial rise infertility–if not to full replacement level (slightly more than two children per woman), then at least to a level that would moderate the tempo of population decline and make population aging easier to cope with. An additional counter to declining numbers, if not significantly to population aging, could come from net immigration. This is the demographic future assumed in the UN medium‐variant projections for countries and regions currently of very low fertility. Thus, for example, in Europe over the period up to 2050 fertility is assumed to rise to 1.85 and net immigration to amount to some 32 million persons. The UN projections also anticipate further improvement in average life expectancy–from its current level of 74 years to 81 years. This factor slows the decline in population size but accelerates population aging. Under these assumptions, Europe's population would decline from its present 728 million to 653 million by 2050. At that time the proportion of the population over age 65 would be 27.6 percent, nearly double its present share. Demographic change of this nature is not a novel prospect. It was envisioned in a number of European countries and in North America, Australia, and New Zealand in the late 1920s and early 1930s. Concern with the possible economic and social consequences generated much discussion at that time among demographers and social scientists at large and also attracted public attention. Possible policy measures that might reverse the downward trend of fertility were also debated, although resulting in only hesitant and largely inconsequential action. The article by D. V. Glass reproduced below is an especially lucid and concise treatment of demographic changes under conditions of low fertility and their economic and social implications. It appeared in Eugenics Review (vol. 29, no. 1, pp. 39–47) in 1937 when the author was 26 years old. Glass's line of argument is broadly representative of the main focus of demographic analysis in the mid‐1930s on aspects of population dynamics, applying the then still novel analytical tool of the stable population model. It also echoes the work of economists then witnessing the great difficulties capitalist economies faced in adjusting to structural changes in consumer demand and labor supply. While Glass addresses these issues primarily with reference to England and Wales, he sees the issues as affecting all industrialized countries. The Malthusian problem of relentless population growth he persuasively declares to be irrelevant for these countries. The Western world faces the opposite problem: population decline, a trend only temporarily masked by the effects of an age distribution that still has a relatively high proportion of women in the child‐bearing ages, reflecting the higher fertility level of the past. A stationary population, Glass cogently argues, is to be welcomed, and he considers the absolute size at which zero growth would be achieved relatively unimportant. In contrast, a continuous population decline would have “thoroughly disastrous” results in an individualist civilization and in “an unplanned economic system.” And, he concedes, somewhat quaintly, that sustained below‐replacement fertility would pose a great problem “even in a country in which the means of production were owned communally.” Glass's conclusions about the reversibility of low fertility are as pessimistic as those of most informed observers today. Still, he sees hope in a future “rationally planned civilization” that would “produce an environment in which high fertility and a high standard of life will both be possible.” In this context, high fertility means the level necessary to sustain the population in a stationary state. By present‐day standards the level Glass calculates as needed for long‐term zero growth is indeed fairly high: 2.87 children per woman. But that figure reflects the fact that, when he wrote, mortality up to age 50 was still fairly high and fertility occurred almost wholly within marriage; it also assumes zero net immigration. In the last 70 years much has changed in each of these three components of population dynamics, both in England and Wales and in the rest of Europe. Still, Glass's commentary remains highly relevant to the discussion of the problems of low fertility today. David Victor Glass (1911–78) was associated with the London School of Economics throughout much of his scientific career. He followed R. R. Kuczynski as reader in demography in 1945 and became professor of sociology in 1948. His work on demography, population history, and population policy had already made him one of the most influential demographers in pre‐World War II Britain. After the war he rose to international prominence through pioneering work on the Royal Commission of Population; through his research on historical demography, the history of demographic thought, and social mobility; and through founding, in 1947, the journal Population Studies, which he edited until his death.  相似文献   

7.
本文建立一种引入迁移人口的人口预测模型,该模型将根据年龄别净迁移率测算出各年龄段分性别的净迁移人口,并将模型划分为零岁人口预测模型和非零岁人口预测模型分别进行预测。根据此模型可预测人口总数、各年龄段人口总数、劳动人口总数、老少比变动情况及各年龄段女性人口数等指标。  相似文献   

8.
Conventional measures of long‐term population growth such as the intrinsic growth rate and the net reproduction rate assume migration rates to be zero. We develop expressions for analogous measures that register the impact of net migration rates, and we develop a simple method of estimating their values. Applying these new measures to data for developed countries shows that allowance for migration raises net reproduction rates by 0.2‐0.3 in areas of overseas European settlement and by approximately half as much in Northern and Western Europe. The newly defined intrinsic growth rates in Eastern Europe are exceptionally low at ‐1.7 percent to ‐2.4 percent per annum. In contrast, the migration‐adjusted intrinsic growth rate of the United States exceeds those of Asia and Latin America. The formulas and estimation procedures described should allow a more precise understanding of the implications of current migration patterns for long‐term growth prospects.  相似文献   

9.
10.
Evidence on the demographic components of city growth in the global South is scarce, and the role played by international migration is neglected. We analyze the importance of recent international migration in cities, compare it with that of internal movements, and evaluate the growth contribution across national contexts and the urban hierarchy. Combining individual-level census data and geographic master files of metropolitan areas with indirect demographic estimation techniques, we cover 377 cities in seven countries. It is found that, in almost one third of cities, population change and replacement has been mainly determined by migration. The international component was larger than the internal one in more than half of cities. Whereas internal migration tends to decrease with rising city size, international movements tend to increase. Positive net international migration substitutes for the net losses from domestic movements in large cities, but complements the gains in intermediate-sized cities.  相似文献   

11.
A nation’s population is redistributed through migration flows and counterflows between its constituent subnational areas, resulting in a geographical pattern of net migration gains or losses which may change from one time period to another. Migration effectiveness is the indicator commonly used to measure net migration as a proportion of gross migration turnover for any territorial unit. This paper explores the effect of net migration in two different countries, Australia and the United Kingdom, using measures of migration effectiveness computed from period-age migration data sets for a system of city regions assembled for four consecutive five-year periods in each country. While the evidence suggests that the overall effectiveness of net migration has declined over the 20-year period in both countries, marked similarities and contrasts are apparent in the spatial patterning of migration that together provide useful analytical insights into the changing space economies of the two countries.  相似文献   

12.
This paper compares age-specific mortality rates in England and Wales with those of New Zealand. Differences in rates are greatest at the younger age groups, and are particularly high for infants under 1 year and children between 1 and 5 years. The age-specific mortality rates for females under 25 years and for males under 35 years are analysed by causes of death in order to discover where the main differences between the two countries occur, and for infant mortality in England and Wales a further analysis has been made by social class. The greatest room for improvement in England and Wales mortality rates, as compared with New Zealand rates, is at ages under 5 years, and in infant mortality in particular the greatest differences between England and Wales and New Zealand rates by causes of death are for those causes usually associated with environmental influences.  相似文献   

13.
In the course of a sample survey of the adult population of eight cities in southcentral Brazil conducted in 1959 and early 1960, material was obtained respecting total family size after ten or more years of marriage. This was analysed in order to determine what variations in mean family size could be observed in relation to class status and social mobility. The results generally corroborate those of J. Berent for England and Wales–that is, that fertility is inversely related to class status, and that for a given class, the lower the class of origin, the higher the fertility. There was no confirmation, however, of J. Goldberg's findings in Detroit that the inverse relationship between class and fertility is due to the presence in urban populations of the rural-born, and suggestions are put forward which may explain this result in Brazil. A tentative estimate suggests that the net effect of social mobility had been to reduce the sample's total births by something of the order of 3 per cent.  相似文献   

14.
There are long‐standing concerns over low fertility levels in Europe and an increasingly important debate on the extent to which migration can compensate for below‐replacement fertility. To inform this debate, a wide array of indicators have been developed to assess the joint influence of fertility, mortality, and migration on birth replacement and intergenerational replacement. These indicators are based on various models and assumptions and some are particularly data demanding. In this article we propose a simple method to assess how far migration alters the extent of replacement for a birth cohort as it ages. We term the measure the overall replacement ratio (ORR). It is calculated by taking the size of a female birth cohort at selected ages divided by the average size of the cohorts of mothers in the year of birth. We present estimates of the ORR for a range of European countries representing different replacement regimes. We demonstrate that for many countries net migration has become a key factor in their population trends during the last few decades.  相似文献   

15.
In this note an attempt has been made to estimate the incompleteness of birth registration in Great Britain in the first decades of civil registration. For Scotland, registration appears to have been reasonably complete after 1861. For England and Wales, however, there seems to have been a considerable initial deficiency, with a consistent improvement over time and no sudden change following the 1874 amending Act. The estimates given in this note suggest that, to allow for under-registration in England and Wales, registered births should be multiplied by a factor of about 1.094 for the period 1841-5, the factor falling steadily to 1.o by 1880. It should be emphasized that the methods of estimation used in this note are indirect and the results very approximate. In the view of the writer, the estimates tend in general to be somewhat too low, especially for the earlier part of the period covered.  相似文献   

16.
Little is known about the environmental implications of long-term historical trends in household size. This paper presents the first historical assessment of global shifts in average household size based on a variety of datasets covering the period 1600–2000. Findings reveal that developed nations reached a threshold in 1893 when average household size began to drop rapidly from approximately 5.0 to 2.5. A similar threshold was reached in developing nations in 1987. With the notable exceptions of Ireland, and England and Wales in the early 1800s, and India and the Seychelles in the late 1900s, the number of households grew faster than population size in every country and every time period. These findings suggest accommodating housing may continue to pose one of the greatest environmental challenges of the twenty-first century because the impacts of increased housing present a threat to sustainability even when population growth slows. Future research addressing environmental impacts of declining household size could use an adapted IPAT model, I = PHoG: where environmental impact (I) = population × personal goods (P) + households × household goods (HoG).  相似文献   

17.
It is generally accepted by demographers that cohort-component projection models which incorporate directional migration are conceptually preferable to those using net migration. Yet net migration cohort-component models, and other simplified variations, remain in common use by both academics and practitioners because of their simplicity and low data requirements. While many arguments have been presented in favour of using one or other type of model, surprisingly little analysis has been undertaken to assess which tend to give the most accurate forecasts. This paper evaluates five cohort-component models which differ in the way they handle migration, four of which are well known, with one—a composite net migration model—being proposed here for the first time. The paper evaluates the performance of these five models in their unconstrained form, and then in a constrained form in which age–sex-specific forecasts are constrained to independent total populations from an extrapolative model shown to produce accurate forecasts in earlier research. Retrospective forecasts for 67 local government areas of New South Wales were produced for the period 1991–2011 and then compared to population estimates. Assessments of both total and age-specific population forecasts were made. The results demonstrate the superior performance of the forecasts constrained to total populations from the extrapolative model, with the constrained bi-regional model giving the lowest errors. The findings should be of use to practitioners in selecting appropriate models for local area population forecasts.  相似文献   

18.
The nature of the roots for a set of fertility functions were explored in this study, resulting in tables from creation of a family of model fertility schedules. These model fertility schedules accurately represent the full range of age structures of fertility in large populations; they have close fit to various accurately recorded fertility schedules of very different form. The text for the tables includes discussions of: 1)the basis for the fertility schedules, 2)the age structure of the proportion ever married (G(a) specified by 2 parameters, 3)single parameter specified age structure of marital fertility, 4)the similarity of model schedules of age specific fertility to the age pattern of fertility in actual populations, 5)model fertility schedules' suitability during changing nuptuality. Possible uses of the schedules and their application to different countries (England, Wales, Peru) are also described.  相似文献   

19.
Delavande A  Rohwedder S 《Demography》2011,48(4):1377-1400
Cross-country comparisons of differential survival by socioeconomic status (SES) are useful in many domains. Yet, to date, such studies have been rare. Reliably estimating differential survival in a single country has been challenging because it requires rich panel data with a large sample size. Cross-country estimates have proven even more difficult because the measures of SES need to be comparable internationally. We present an alternative method for acquiring information on differential survival by SES. Rather than using observations of actual survival, we relate individuals’ subjective probabilities of survival to SES variables in cross section. To show that subjective survival probabilities are informative proxies for actual survival when estimating differential survival, we compare estimates of differential survival based on actual survival with estimates based on subjective probabilities of survival for the same sample. The results are remarkably similar. We then use this approach to compare differential survival by SES for 10 European countries and the United States. Wealthier people have higher survival probabilities than those who are less wealthy, but the strength of the association differs across countries. Nations with a smaller gradient appear to be Belgium, France, and Italy, while the United States, England, and Sweden appear to have a larger gradient.  相似文献   

20.
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