Reuters

Americans have a habit of talking about poverty as if it were a deep gulch somewhere at the fringe of the U.S. economy. We imagine a few unfortunate souls fall in forever—but only a few.

The truth, though, is almost the exact opposite, as Washington University in St. Louis professor Mark Rank recently reminded New York Times readers. "Contrary to popular belief," he wrote over the weekend, "the percentage of the population that directly encounters poverty is exceedingly high." Between the ages of 25 and 60, Rank has found, almost 40 percent of Americans will live at least one year below the poverty line. Yet over time, most also pull themselves back above of it.

To get a slightly better picture of how poverty tends to touch U.S. lives, I asked Rank for a peek at his most recent figures, which will be published in an upcoming book co-authored with Cornell's Thomas Hirschl and the University of South Carolina's Kirk Foster. As in his past work, Rank and his collaborators have analyzed decades of data from the Panel Study of Income Dynamics to find out when Americans are most likely to suffer from poverty and how long they generally remain in it.

Instead of a deadly gulch, impoverishment turns out to be more like a roadside ditch. Many crash into it, especially while young, but most eventually recover. So while 38.9 percent of Americans will live at least year under the official poverty line between ages 25 and 60, just 11.6 percent will spend five years or more impoverished.