Fertility rates fall.

人口出生率下降。

youdao

There are lots of social explanations of why fertility rates fall as countries become richer.

很多理论在社会层面解释了为何越富裕的国家生育率越低。

youdao

Inequality tends to rise as fertility rates start to fall.

ECONOMIST: Free exchange

Economic growth would be around 3 % per year, as populations became richer they would see a fall in fertility rates, just as countries which became rich in the past did.

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