My first reaction was (again) irritation at the waste of women in Japan, but it's more than that. Yes, it's true that Japanese women lag behind (postgraduate studies, management, politics, ad nauseum), but this PhD problem extends to men, too. Why so low in Japan?
1) Fewer students require fewer academic staff.
2) Japanese companies want inexperienced youngsters who can be moulded into cookie-cutter employees.
More from nature.com
below:Japan: A system in crisis
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. The science and education ministry couldn't even sell them off when, in 2009, it started offering companies around ¥4 million (US$47,000) each to take on some of the country's 18,000 unemployed postdoctoral students (one of several initiatives that have been introduced to improve the situation). "It's just hard to find a match" between postdoc and company, says Koichi Kitazawa, the head of the Japan Science and Technology Agency.
This means there are few jobs for the current crop of PhDs. Of the 1,350 people awarded doctorates in natural sciences in 2010, just over half (746) had full-time posts lined up by the time they graduated. But only 162 were in the academic sciences or technological services,; of the rest, 250 took industry positions, 256 went into education and 38 got government jobs.http://www.nature.com/news/2011/110420/full/472276a.html
PS from Ru: Japan's tertiary education system is ... not ideal. (I can be remarkably restrained when I'm in the mood.) The country has good universities, but apart from Todai they simply don't/can't compete on the global stage. It's enough to make a strong woman cry.
Source of graph:http://oecdeducationtoday.blogspot.co.uk/2014/10/doctorate-degree-holders-take-research.html?m=1