I found Tania Branigan's Guardian article on China's coming demographic spasm really interesting. China's One Child policy means that there's a giant cohort of imminent retirees and a much smaller group of young adults of working age who'll have to support them. Combine that with the tradition (and law) of filial piety, which puts responsibility for the elderly on their children, increased life-expectancy, and a shame-taboo against retirement homes, and you've got the makings of some very turbulent times ahead.
China's economic miracle has been fuelled by its "demographic dividend": an unusually high proportion of working age citizens. That population bulge is becoming a problem as it ages. In 2000 there were six workers for every over-60. By 2030, there will be barely two.
Other countries are also ageing and have far lower birth rates. But China is the first to face the issue before it has developed – and the shift is two to three times as fast.
"China is unique: she is getting older before she has got rich," said Wang Dewen, of the World Bank's China social protection team.
Tens of millions of workers have migrated to the cities, creating an even worse imbalance in rural areas which already suffer low incomes, poor public services and minimal social security.
Most old people there rely on their own labour and their children. China not only needs to support more older people for longer, but to extend support to new parts of society. World Bank researchers point to promising advances, such as the national rural pension scheme and the expansion of health insurance.
China can help deal with increased costs by raising its retirement age; at present, only about a fifth of urban women are still working at 55. Improving education should also raise productivity. Some experts believe such measures will be enough to wipe out the "demographic debt". Others wonder if China will begin to welcome immigrants.
China faces 'timebomb' of ageing population
