Retirement quandary: more retirees at younger ages, living longer.

The authors examine trends in age at retirement and life expectancy in the United States. "We used labor-force data from the Current Population Survey...to calculate the percentage change in labor-force participation rates for five-year birth cohorts over a series of five-year intervals.... Using these percentage changes, corrected for mortality during each five-year interval, we calculated the average age at retirement (median age) from the early 1950s to the late 1990s."