There is also this to consider: China pursued, and maybe is still pursuing, population control very aggressively with its "One Child Policy". And now its population is aging... soon there will be more old people than young ones. I have also heard that in Japan schools were closed due to the *lack of children* ... it's almost unimaginable. But maybe it's due to migration from small towns to big cities rather than any drastic drop in birthrate. Singapore used to have a "Stop at Two" campaign to limit family sizes, and now is belatedly reversing it... So... China and Far East Asia rises for a while, then stalls because there are not enough young people...