U.S. workers seem to be responding to worries about retirement assets by planning to work longer rather saving more.

The percentage of workers who said they are very confident about having enough to live comfortably throughout retirement fell to 13%, from 16% in 2010, and the percentage who said they are not confident increased to 27%, from 22%.

Researchers at Mathew Greenwald & Associates Inc., Washington, and the Employee Benefit Research Institute, Washington, have reported those figures in a summary of results from the latest Retirement Confidence Survey, which drew on telephone interviews with 1,004 U.S. Retirement clockworkers ages 25 and older and 254 U.S. retirees

Only 68% said they or a spouse had tried to save for retirement, down from 69% in 2010, and down from 75% in 2009.

The percentage of workers who said it is reasonably possible for them to save $25 per week for retirement fell to 62%, from 66% in 2004.

The percentage of workers who expect to retire after age 65 increased to 36%, from 25% in 2006, and the percentage who expect to work in retirement increased to 74%, from 70% in 2010.

The researchers found that workers with less than $100,000 in savings are especially nervous about retirement.

“In total, more than half of workers (56%) report that the total value of their household’s savings and investments, excluding the value of their primary home and any defined benefit plans, is less than $25,000,” the researchers report.

Just 42% of the workers said they or their spouses had tried to calculate how much money they might need to save to live comfortably in retirement.

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