When are you going to retire? Later than you figured.

Here’s a really big number: $2 trillion. According to the front page of yesterday’s Washington Post,  that’s how much disappeared from Americans’ retirement savings in the last 15 months. The upshot: Americans are going to have to work longer.  

Even before the October meltdown, one in five respondents to an AARP Financial survey  had pushed back their retirement date, and most didn’t expect to be able to retire when they wanted to. On the other hand, over a quarter also spent more time watching reality TV in the last month than they’d spent planning for retirement in the last decade, so maybe they’re not all that worried. The more time they spend on the job, the less worried they should be.  

“That’s not more hours per week but more years per life. Do that, and the impact on retirement savings will dwarf anything you can get from shifting around investments, whether times are good or bad,” counsels Mitchell Schnurman, business columnist for the Fort Worth Star-Telegram. “The choice of retirement age is the most important portfolio choice most workers will make,” confirms a 2006 study by the Urban Institute. Lower-income workers have the most to gain: five additional years of work would double their annual retirement income. 

Older Americans who stay on the job will have plenty of company. The number of full-time workers over age 55 grew from about 22 percent in 1990 to nearly 30 percent in 2007, according to the Bureau of Labor Statistics. By 2016, the bureau predicts, the number of workers age 65 and over will soar by more than 80 percent. This is a mixed blessing, but flextime and part-time work should ease the burden for many. And as my subjects demonstrate, the benefits extend way beyond the pocketbook. Schnurman concurs: “Older workers tend to be more engaged, more healthy, more happy.”