This trend will benefit not just fortunate oldies but also, in some ways, society as a whole. Growth will slow less dramatically than expected; government budgets will be in better shape, as high earners pay taxes for longer. Rich countries with lots of well-educated older people will find the burden of ageing easier to bear than places like China, where half of all 50-to-64-year-olds did not complete primary-school education.
At the other end of the social scale, however, things look grim. Manual work gets harder as people get older, and public pensions look more attractive to those on low wages and the unemployed. In the lexicon of popular hate-figures, work-shirking welfare queens breeding at the taxpayer’s expense may be replaced by deadbeat grandads collecting taxpayer handouts while their hard-working contemporaries strive on.
Nor are all the effects on the economy beneficial. Wealthy old people will accumulate more savings, which will weaken demand. Inequality will increase and a growing share of wealth will eventually be transferred to the next generation via inheritance, entrenching the division between winners and losers still further.