Confidence in retirement security has not improved as the economy and stock markets picked up over the last three years and actually is lower now than during the worst of the Great Recession downturn, according to the Pew Research Center.

It found that 38 percent of adults surveyed are not too confident or not at all confident they will have enough income and assets in retirement, compared with 25 percent surveyed in February and March 2009, when the stock market hit its recent low point.

The concern is highest among those in their late 30s, while there has been some improvement among those in their late 50s compared with the earlier survey, Pew reported—among that younger group, 53 percent expressed lack of confidence. It said that finding was consistent with recent data from the Federal Reserve Board finding the greatest retirement concerns among those in their late 30s to early 40s.

One reason is that the median net worth for that group fell more in the last 10 years than for any other age group, it said, a loss largely due to declining home values. Those older than that group tended to have more assets elsewhere to offset that decline, while those younger tended to not suffer as much from declining home values, in many cases because they did not yet own homes.

Pew added that concerns about retirement security have been growing for at least 10 years, beginning before the recession. It added that better-educated and higher-income individuals are more likely to be confident.