Americans still haven’t figured out how to make their retirementmoney last.

A survey that compared workers’ understanding from 10 years agoof how much they could safely withdraw from their retirement nesteggs without running out of money, versus how much today’s workersbelieve is a safe percentage, has revealed that while participantsare improving, they’re still a long way from knowing what that safeincome level is.

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The survey, released by Ipsos Public Affairs, found that 77percent of Americans over the age of 40 do not know how much oftheir retirement savings they can safely spend each year withoutrunning the risk of outliving their assets.

In 2006, before the Great Recession, 90 percent of Americans didnot know a safe withdrawal rate, and believed that 10 percent wasacceptable. Now 23 percent of respondents realize they should keepwithdrawals to below five percent of their retirement savings peryear.

In general, experts say that typical participants shouldn’t takemore than 4 percent per year from their retirement plans. But thatdoesn’t mean that those participants are aware of that; 19 percentof respondents said they didn’t know how much to withdraw each yearfrom their retirement savings to avoid running out of money duringretirement.

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And 31 percent of all respondents actually think they can getaway with spending 10 percent—or even more—of their savings eachyear. Historic investment returns would predict that, at that rate,retirees risk running out of money in about 11 years or less. Andthat’s a lot shorter period than their projected lifespans duringretirement.

The good news is that people are trying to figure out ways toturn their savings into lifetime income, with 58 percent expressingthat interest. Ten years ago, only 25 percent said they wereinterested in doing so.