The issue of population probably didn’t make it onto the agenda of the November plenary meeting held by the Chinese leadership to discuss future economic policy. Yet of all the economic challenges China will be compelled to address in the next few years, accelerated population aging definitely tops the list. In any case, the U.N.’s authoritative projections leave no room for doubt about where the country will be in 2040. Between now and then, the U.N. expects the median age to rise by more than eleven years to 46; the working-age population to shrink by 10 percent; the 15-to-44 age group to lose 200 million members, with the 65-and-over group gaining as many; and the ratio of workers to retirees to plummet from 18 to 2 at present to just 5 to 2. So the graying of China is likely to go extremely fast—even faster, in some respects, than the process under way in Europe.