Japan's economy and society face a rapid aging of the population. The propor- tion of the elderly (defined here as those 65 years of age or older) in the total population, which was 4.9 percent in 1950-very low by international stan- dards-rose to 14.8 percent in 1995. The ratio is projected to rise further, to over 25 percent by 2020, which would make it among the highest in the major OECD countries.' The rapid aging of the Japanese population reflects the high rate of economic growth during the postwar period and associated structural changes in industry and society, particularly in family structure.