There are several reasons to be concerned about the below population replacement fertility levels in all of Europe and about half the world's population, including China and Japan.

在整个欧洲和几近半数的世界人口中，包括中国和日本，对于下降的人口更替生育水平有一些原因可以考虑。

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In France the fertility rate is already around two children per female, not far short of the “replacement rate” which keeps population numbers steady.

法国的人口出生率已经达到每个家庭两个孩子，离保持人口数量稳定的“替代率”相差无几。

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The fertility rate is the number of children a woman can expect during her lifetime; 2.1 is the replacement level, the point at which the population stabilises.

人口出生率是指女性一生预期生养的儿童数目；2.1是更替水平，人口在这一点上保持稳定。

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Still, because the current level is far below the level of 2.07 required to prevent population replacement, the result is net decline.

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Singapore's total fertility rate of 1.2, which represents the number of children that would be born to a woman if she were to live to the end of her child-bearing years, has been below the population replacement rate for more than three decades.

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Larry Summers, Barack Obama's main economic adviser, has noted that current annualised vehicle sales of about 9m are well below the 14m necessary for replacement and rising population, while annualised housing starts are about a quarter of the rate needed to support the forming of new households.

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