The good news is that at least one segment of the population has seen its employment statistics actually rise in this economic downturn.

The bad news?

That segment is older Americans, many of whom are only working because they're afraid they don't have enough savings to retire, the Washington Post reports.

Since the start of the recession, the number of workers aged 55 and older has shot up by 3.1 million, or 12%. That's in part because the country is getting older, and because jobs have grown less physically demanding, allowing people to work longer.

But another major factor is that 401(k)s have largely replaced company pensions, making retirement riskier—an August AARP poll showed that 57% of Americans older than 50 had become less confident about their ability to retire since the recession.

"Fear is a wonderful motivator," says one retirement researcher. "Some of these people are just clinging by their fingernails to jobs."

This post originally appeared at Newser.