Japan's birth rate has been low for many years, while life expectancy has been high. The result is a demographic structure that is fantastically skewed. This is best conveyed by the statistic that sales of diapers for incontinent older people now exceed sales for babies.
Piled onto this well-known problem are two others: many younger Japanese women are not getting married, and a significant number of young Japanese, especially men, are hiding for years -- even decades -- in their bedrooms, refusing to see even their parents, who leave meals outside their doors. Hikikomori, as the Japanese call it, is thought by sociologists to affect up to 1 million young men.