Prisons and jails added more than 1,000 inmates each week for a year, putting almost 2.2 million people, or one in every 136 U.S. residents, behind bars by last summer.

Racial disparity persists
The racial makeup of inmates changed little in recent years, Beck said. In the 25-29 age group, an estimated 11.9 percent of black men were in prison or jails, compared with 3.9 percent of Hispanic males and 1.7 percent of white males.

Marc Mauer, executive director of The Sentencing Project, which supports alternatives to prison, said the incarceration rates for black people were troubling.

“It’s not a sign of a healthy community when we’ve come to use incarceration at such rates,” he said.