While the government hopes it can curb the falling birthrate by offering families more financial assistance, one expert says it's the lack of sex, not income, that lies at the root of the country's population problem. Kunio Kitamura, executive director of the Japan Family Planning Association Inc., an entity under the Ministry of Health, Labor and Welfare, said the real problem is the growing number of "sexless" couples. A survey conducted last year of 936 people, aged 16 to 49, conducted by JFPA and Jichi Medical University in Tochigi Prefecture shows that 31 percent were "sexless" -- which the Japan...