About 65% of U.S. workers now expect to delay their retirement by at least a year, up from 54% at the end of 2008.

The Wellesley Hills, Mass., U.S. division of Sun Life Financial Inc., Toronto, has published that finding in its latest Unretirement Index survey report.

Sun Life has based the latest Unretirement Index results on a survey of 1,451 U.S. residents conducted from Aug. 14 to Sept. 14. All of the participants were ages 18 to 66, and all were working full- or part-time.

Because of the current economic environment, 27% of the participants said they now believe they will need to work at least 5 years longer than they had previously expected.

Only 28% said they were very confident that they had done a good job of preparing for retirement, and just 22% were very confident they would be able to take care of medical expenses after retirement.

A year ago, the most popular reason given for planning to work past age 67 was “to stay mentally engaged.” Today, Sun Life says, the leading motivation is “to earn enough money to live well.” About 63% said an important reason to keep working past age 67 is to have access to employer-sponsored health benefits.

The percentage of survey participants who said they are reducing spending has increased to 77%, from 67% at the beginning of the year, and the percentage who said they are reducing debt has increased to 64%, from 55%.