Why the 21st century may not be China's

From the Economist, found via Tigerhawk:

China is still a relatively young country, with a median age of around 30. But, uniquely among developing countries, it is ageing extraordinarily fast, so by 2050 its median age will have risen to about 45. Over the next few decades the ratio of elderly dependants to people of working age will rise steeply, from 10% now to 40% by 2050. From about 2030 the country will have more elderly dependants than children (see chart 8), whereas in most other developing countries the opposite will remain true for the next few decades. China’s pattern of ageing is very similar to that in Japan, Hong Kong, Singapore, South Korea and Taiwan. The difference is that in China this is happening at a time when the country is still relatively poor.
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So there is now an economic, as well as a human-rights, case for relaxing the country’s “one-child policy”. Many Chinese academics think it can be only a matter of a few years, but the government seems in no hurry. “Family planning”, as it likes to call the policy, is seen as a success, easing pressures on the environment and resources of all kinds. There is no explicit population target, but the latest forecasts suggest that numbers will keep growing from about 1.3 billion now to a peak of around 1.46 billion by 2030 and then start declining gently.

In fact, even if the restrictions were loosened immediately the birth rate might not tick up by very much. In the big cities many people are already leading the sort of lives that have brought down fertility in richer countries.