It takes but a moment for the piano to sound a note after a key is struck, and it takes months before heavy snow storms result in floods; but it takes decades before changing birth rates change the size of a population. Moreover, it is not solely the birth rate (births per 1,000 population) that affects the size: if people five longer, the population must obviously grow. The US population is now growing and short of violent disaster, will continue to do so for some decades to come.
From this it is often quite wrongly concluded that there is a population explosion in the US. This is like fearing a flood because the river level is still slowly rising after the spring run-off, when a look at the dry mountains would reveal that what is really threatening is a drought.
Thus, to gauge the future of a population, one should not look at its present size or even at its present trends in size, but at its fertility rate
¾the number of births per 1,000 women aged 15-44. A glance at its history will dispel many widespread myths.Demographers know very little about the causes of the ups and downs in fertility rates; just about the only firm conclusion is that fertility rates drop very rapidly as a country industrializes (presumably because children turn from an economic asset to an economic liability
¾from an extra hand to bring in the harvest to a problem how to pay for a college education).GRAPHIC: A02_86.01.TIF
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Vol. 13, No. 6
Newsletter: Access to Energy Newsletter Archive Volume: Issues Issue/No.: Vol. 13, No. 6 Date: November 29, 2004 03:59 PM Title: Review of a review
Copyright © 2004 - Access to Energy Newsletter Archive
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