.</ref> Chuo University professor Yoshiaki Yoshimi states there were about 2,000 centers where as many as 200,000 Japanese, Chinese, Korean, Filipino, Taiwanese, Burmese, Indonesian, Dutch and Australian women were interned. Ikuhiko Hata, a professor of Nihon University, estimated the number of women working in the licensed pleasure quarter was fewer than 20,000 and that they were 40% Japanese, 20% Koreans, 10% Chinese, with others making up the remaining 30%. According to Hata, the total number of government-regulated prostitutes in Japan was only 170,000 during World War II.