A larger share of 65-year-old men worked in 1940 than their counterparts do today -- about 70 percent in 1940 compared to roughly 30 percent today. The fall in what reseachers call the labor force participation rate of men would be even more dramatic, say economists, if the figures were adjusted to account for increases in life expectancy over the past 60 years.

• In 1997, men turning 65 could anticipate another 16 years of life; in 1940, men who could expect to live another 16 years were 60 years old.

• Adjusting the labor force participation rate to account for the increase in longevity -- and assuming older men are as able to work as their younger counterparts in 1940 -- the rate for 60-year-olds in 1940 was close to 80 percent -- 10 percentage points greater than the traditional calculation of 70 percent for 65-year-olds.

• The sharpest drop in the participation rate of older male workers occurred soon after 1961, when early retirement Social Security benefits were made available to men at age 62, and at about the time that Medicare became accessible (1966).

• During the early 1980s, the labor force participation rate stabilized and has increased slightly since then; but adjusted for increasing life expectancy, it has continued to drop, albeit at a slower rate than in the 1960s and 1970s.

The rapid decline appears to be substantial evidence that incentives created by public programs for the elderly and near-elderly have an even more powerful influence on retirement decisions than is apparent under the traditional measure, conclude researchers.

Source: Eugene Steuerle and Christopher Spiro, "Adjusting for Life Expectancy in Measures of Labor Force Participation," Straight Talk No. 10, October 30, 1999, Urban Institute, 2100 M Street, N.W., Washington, D.C. 20037, (202) 833-7200.

For text http://www.urban.org/retirement/st/Straight10.html