While people are trying  —  and often failing  —  to save for retirement, they’re not really thinking about how they’ll make whatever money they will have stretch once they leave the workplace.

That’s according to a Harris poll conducted for Pentegra Retirement Services that found that more than half (56 percent) of those who have managed to accumulate some retirement savings have no plan for how they’ll access the money and make it last in retirement. In fact, one out of every five hasn’t even thought about it.

Their average target age for retirement is 66, but 20 percent don’t plan to retire at all. They want to start drawing Social Security benefits at age 67, and those still in the workplace estimate they’ll need an average of $3,200 per month in income to live.

But 19 percent say they’ll need considerably more  —  $5,000, to be exact. Considering that, according to the Social Security Administration, Social Security benefits average only about $1,300 per month, that’s a lot of ground to be made up by savings or some other source.

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Even that $5,000 figure may not be enough, although it’s likely closer to the truth. “Based on the average household income of $52,000, this number may seem practical at first glance, but many people do not factor in having to pay for health coverage and cost-of-living increases when estimating how much they will realistically need,” Rich Rausser, senior vice president of client services at Pentegra Retirement Services, said in a statement.

Then there’s the question of how to transform retirement savings into monthly income —something many people don’t even understand. Most people either don’t understand or are completely unaware of many of the options for receiving the money they’ve saved once they start to draw on it for living expenses.

Only 24 percent of respondents said they were very familiar with lump-sum payouts. Slightly more, 29 percent, said they were very familiar with routine quarterly or monthly payments, while just 23 percent said they were very familiar with annuities that would provide guaranteed monthly income during their lifetimes. Even fewer, only 17 percent, knew that annuities could do that for themselves and their beneficiaries. And one out of four of those still working didn’t even know that was an option.