Saving For Retirement: How Much Do You Need?

By some counts, fewer than half of Americans have ever tried to calculate how much they'll need for retirement. And those who do? Half tell pollsters they just guessed.

A poll for NPR, the Robert Wood Johnson Foundation and the Harvard School of Public Health finds retirement is proving more difficult than expected for many Americans, in large part because they haven't saved enough. So we set out to ask: How much do you need?