American workers not only don’t save enough money toward retirement, they really don’t know how they’ll turn what they do save into income once they leave the workplace.

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According to the "TIAA 2016 Lifetime Income Survey," 58 percent of respondents feel confident that they can successfully turn their retirement savings into income after they stop working. And, ironically, only 35 percent are concerned that they might run out of money during retirement — despite the facts that only 46 percent even know how much they’ve saved and even fewer — just 35 percent — know how much monthly income they’ll have in retirement.

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Only 28 percent of those who have analyzed how their savings will translate into retirement income are concerned about running out of money after they stop working, as opposed to 40 percent of those who have not done the analysis. And while 49 percent say that their retirement plan’s top goal should be to provide guaranteed monthly income in retirement, 41 percent are unsure if their current plan provides an option for lifetime income.

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And they’re not saving enough; 41 percent save 10 percent or less, despite experts recommending at least 10–15 percent. They also underestimate how much they’ll need; experts say 70-100 percent of current income, but most workers think they can get by on less than 75 percent of what they make now for a comfortable retirement.

And, of course, 28 percent aren’t saving anything at all, but only 47 percent of those are concerned that they’ll run short once they’re retired.

When it comes to actually turning whatever savings they have into monthly income, workers are looking at a range of options. But, as might be expected, how many options they have available depends to a large extent on how much money they make.

People with incomes over $100,000 a year are more likely to have options than people with incomes under $50,000 a year.

For instance, 69 percent of those at the higher income level plan to withdraw savings from a retirement plan, compared to 41 percent of those at the lower level, and they are more likely to get payments from a pension plan (40 percent compared with 19 percent).

They are also more likely to plan on income from annuities (27 percent compared with 10 percent).

Overall, the great majority — 73 percent — of respondents plan to use Social Security, while 29 percent will use funds from a defined benefit pension plan. Fifty-four percent are looking at withdrawals from retirement accounts like a 401(k), 403(b) or IRA, despite the fact that they could possibly outlive those savings. Just 14 percent overall plan to use annuities.