Birth rate decreased:
By 2100, 183 of 195 countries and territories will have fertility rates below replacement levels, according to projections published last year in The Lancet by an international team of scientists.
Their modelling shows a particularly steep population decline in China, which is projected to drop from 1.41 billion today to about 730 million by 2100. If this happens, the population pyramid flips. China will no longer support fewer retirees based on younger workers, and there will be as many 85-year-olds as there are 18-year-olds.
Demographers point out that the total fertility rate, or the number of children an average woman of childbearing age has, is declining. If this number drops below 2.1, the overall size of the population will begin to decline. "This change may take decades to occur, but once it begins, the population decline will spiral exponentially." The New York Times said.
But at present, the total fertility rate in many countries simply does not reach this level. Birth rates in countries such as the United States, Australia and Canada hover between 1.5 and 2. In populous countries such as India and Mexico, the total fertility rate has also fallen or is falling below 2.1.
To Encourage fertility
policies:
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