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Clift E  Cohn B 《Newsweek》1993,122(19):40-41
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"This study analyzes the importance of children in the care of elderly populations in rural communities [in Mexico].... In particular, the perception of elders about the value of their children is analyzed, especially the role children play in their economic contribution to the household or their instrumental value to it at different stages of their lives.... With respect [to] the condition in which children support their parents in their old age the economic assistance given was studied too. Finally, the preference regarding family size of those 60 years or older [is] given, as well as the view points of women on the need to control fertility and reduce family size. Three different types of cost are studied: the economic cost of supporting and caring for children, the emotional cost of their upbringing and the health cost of multiple pregnancies and births." (SUMMARY IN ENG)  相似文献   
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Population experts appear to be reaching a consensus that there has been a perceptible decline over the last decade in the growth of the world's population. The decline is accounted for by the "new demographic transition" in the less developed countries (LDCs). The decline in fertility rates began in the 1950s in some LDCs and became more widespread during the 1970s. The process has not yet begun in many of the LDCs. During the 1960s it was observed that the declines in birth rates (to levels of 30 of less per 1000) were occurring mostly in small countries. Many of these countries were islands with levels of social and economic development above the developing country average. The key question is whether the recent downward trend in fertility in LDCs will continue, stabilize at the current level, or rise again. A primary concern about the future is that the poorer and less developed countries will end up with an increasing share of the world's population, with the share of the developed countries declining from 34% to 22% over the 1950-2000 period. Considerable differential exists in demographic growth patterns among various regions. The 12 largest LDCs (China, India, Indonesia, Brazil, Bangladesh, Pakistan, Nigeria, Mexico, Vietnam, Philippines, Thailand, Turkey) contain 55% of the current world population, and the fertility decline of these nations is expected to have the maximum impact. 7 of these countries have had fertility declines of 14-35%. The force of the "population momentum" must also be considered. Most developing country populations have a young age distribution with considerable potential for population growth even after the fertility level reaches a replacement level and the net reproduction rate equals 1.  相似文献   
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