From Nature:

Of all the countries in which to graduate with a science PhD, Japan is arguably one of the worst. In the 1990s, the government set a policy to triple the number of postdocs to 10,000, and stepped up PhD recruitment to meet that goal. The policy was meant to bring Japan’s science capacity up to match that of the West — but is now much criticized because, although it quickly succeeded, it gave little thought to where all those postdocs were going to end up.

Academia doesn’t want them: the number of 18-year-olds entering higher education has been dropping, so universities don’t need the staff. Neither does Japanese industry, which has traditionally preferred young, fresh bachelor’s graduates who can be trained on the job.

Read the whole article, which also points to an excess supply of Ph.D’s in the U.S. Pointer from Timothy Taylor, who already is nearly as indispensable as Mark Thoma.