The global population is still growing, with the UN predicting that it will peak at 10.3bn in the 2080s.
But in many advanced economies, it's falling, with both rates below the 2.1 needed to keep a population stable.
But why? And how will it affect the global economy?

全球人口仍在增长,联合国预测其将在 21 世纪 80 年代达到 103 亿的峰值。
但在许多发达经济体,人口却在减少,其生育率均低于维持人口稳定所需的 2.1。
然而,原因何在?这又会对全球经济产生怎样的影响?