WORKFORCE PARTICIPATION'S LONG DROP

The thing I don't understand about the U.S. drop in workforce participation rate is how are these people living?  The men's drop is remarkable and started before 1990.  The women are dropping out too, but started later around the year 2000.  This drop for women is contrary to all other major countries!*  In the second figure, note the spectacular rise in workforce participation rate of women in Japan.  The drop of men in Japan's workforce participation rate started in the 1970s, but began to rise again around 1995 and has leveled off in recent years.

* http://blogs.wsj.com/economics/2015/06/26/the-u-s-stands-out-on-labor-force-participation-rates/