David Schenk, 59, of St. Paul, Minn., and a retired teacher, works at an entrance to a ride during his temporary job as an assistant supervisor ticket taker at the Minnesota State Fair in St Paul, Minn., Friday, Aug. 28, 2009. (AP Photo/Craig Lassig)

American workers are turning grayer. Older adults are working longer, and younger adults are delaying entry into the labor force, according to a report from the Pew Research Center.

The nation's work force has been moving in this direction for the past two decades, the report states, but the changes have been exacerbated by the recession, despite the tens of thousands of older workers who have lost their jobs since December 2007. By 2016, 22.7 percent of the labor force will be 55 and older, according to the Bureau of Labor Statistics. From 2006 through 2016, such workers will have increased by 11.9 million.

The key driving forces are the stock market crash and the economic downturn, which are forcing folks to recoup retirement losses; the fact that some people have a simple desire to work longer; and that young adults are remaining students longer, according to the Pew Social & Demographic Trends project.

Many older Americans are working longer because they are healthier and are more likely to live longer than previous generations, said Craig Copeland, a senior research associate at the Employee Benefit Research Institute. And the jobs available are not as physically demanding as they were 10 to 20 years ago.

Older adults emphasize the psychological and social benefits of working. "The reasons for working are beyond pure pocketbook motives," said Paul Taylor, Pew executive vice president.

Other workforce findings

Fewer young workers » In part, that's because there is a growing consensus that Americans need a college education to advance in life. And during the recession, it has been harder for them to find jobs.

Gender divide » Although 27 percent of women say they don't work because of family responsibility, only 3 percent of men respond that way. And older women are more likely than men to say that they are working longer because they need a paycheck. Only a small share of those surveyed, 12 percent, thinks the "ideal situation for a mother of young children is to work full time outside the home."

Older workers are happy workers » Nearly 55 percent of workers age 65 and older say that they are completely satisfied with their jobs, compared with 29 percent of workers younger than 65.

A need to rebuild retirement nest eggs » Many workers specifically say they expect to push back their retirement from 62 to 65 because of stock market losses.

Other work force findings

Fewer young workers » There is a growing consensus that Americans need a college education to advance in life. And during the recession, it has been harder for them to find jobs.

Gender divide » 27 percent of women say they don't work because of family responsibility. Only 3 percent of men respond that way. Older women are more likely than men to say that they are working longer because they need a paycheck. Only 12 percent of those surveyed think the "ideal situation for a mother of young children is to work full time outside the home."

Older workers are happy workers » Nearly 55 percent of workers age 65 and older say that they are completely satisfied with their jobs, compared with 29 percent of workers younger than 65.

Rebuilding nest eggs » Many workers expect to push back their retirement because of stock market losses.