• AP Photo/Seth Perlman
  • Prisoners in a dormitory in Vandalia

In most U.S. jails and prisons, inmates are counted several times a day. But surveys used to measure the nation’s economic well-being aren’t much interested in counting prisoners.

And because the surveys ignore the incarcerated, the data from them “misrepresents the American social condition, especially as it concerns African American men,” sociologist Becky Pettit writes in her recent book, Invisible Men: Mass Incarceration and the Myth of Black Progress. She says the statistics generally cited overstate the levels of education and the economic status of African-Americans.

When the U.S. was founded, slaves were three-fifths of a free person for purposes of apportionment. Slaves and free blacks were enumerated on household rosters, but little information about them was collected before the 1850 census. This obscured the experience of blacks for much of American history, and “they were hardly considered in the design or evaluation of public policy,” Pettit observes in her book.