One in five people who are near retirement age have zero money saved.

Yes, you read that correctly.

The sobering statistic was one of many released by the Federal Reserve on Thursday as part of its report on the economic well-being of U.S. households, which surveyed more than 4,100 people online last year between mid-September and early October.

The study offered a stark reminder that as more Americans are made responsible for their own retirement, most are not saving nearly enough. Overall, 31 percent of people said they have zero money saved for retirement and do not have a pension. That included 19 percent of people between the ages of 55 and 64, or those closest to retirement age.

What's going on here? A lot of people said they rarely thought about retirement, at least not until it was too late. About 41 percent of people ages 18 to 29 said they never thought about retirement planning, a number that understandably declined to 20 percent for people above the age of 60.

But researchers said the dismal saving rates weren't fully explained by lack of caring. They also cited a combination of low resources and poor awareness:

The lack of preparedness is not signaled by a lack of planning alone. Many respondents, particularly those with limited incomes, indicated that they simply have few or no financial resources available for retirement.

For many people, particularly those working part time or earning low wages, the biggest obstacle to a steady retirement savings plan is access. About three-fourths of private sector workers with full-time jobs have access to a retirement plan, but that number drops to 37 percent for part-time workers, according to the Bureau of Labor Statistics.

So, what did workers say about how they expected to cover expenses in retirement? The biggest resource people planned to rely on, whether they had savings or not, was Social Security, which was cited by roughly 45 percent of respondents.

A lot of people said they would just keep working: About one-third of the people surveyed said they delayed their retirement date after the financial crisis. Among the people closest to retirement, those ages 45 and over, that number increases to 41 percent.

Only 18 percent of people said they envisioned having a traditional retirement where they would work full time until a particular date and then stop working completely. About a quarter of respondents said they plan to work as long as possible. And another 18 percent said they expect to take on a part-time job.

Not surprisingly, the most common savings vehicle was a defined contribution plan such as a 401(k) or 403(b), used by 44 percent of the people surveyed. That compares to 18 percent of people who said they were eligible to receive a pension from their employers.

(Correction: This story has been updated to correct that three-fourths of private sector workers with full-time jobs have access to a retirement plan.)

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