It seems that unsustainable population growth won’t be a problem — at least in Japan. For Ailing Japan, Longevity Takes Bite Out of Economy explains:
Japan is wrestling with an unprecedented demographic time bomb. With the average woman bearing 1.33 children, the government projects Japan’s population will start declining in three years. By around 2007, the proportion of the population over 65 will have jumped to 20% from 10% in just 21 years, a rate of graying that’s nearly twice as fast as any other major nation.
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With the world’s longest life expectancy — 85 for women, 78 for men — Japan’s society is aging faster than any other now. But by midcentury, the populations of Italy and Russia are expected to have declined even more drastically. Even China, the world’s emerging economic powerhouse and most populous nation, will age rapidly starting in 2010, with the elderly making up 22.7% of the population by 2050, up from 6.9% now, according to the United Nations Population Division.Such jumps in age, coupled with declines in fertility in virtually every country, have led at least one expert to predict that, after zooming ahead in the next 50 years, the world’s population could begin to decline. That marks a reversal of long-held predictions of unsustainable population explosions.