The figures are based on an analysis of 2011 Current Population Survey data by Northeastern University researchers and supplemented with material from Paul Harrington, an economist at Drexel University, and the Economic Policy Institute, a Washington think tank. They rely on Labor Department assessments of the level of education required to do the job in 900-plus U.S. occupations, which were used to calculate the shares of young adults with bachelor’s degrees who were “underemployed.”

About 1.5 million, or 53.6 percent, of bachelor’s degree-holders under the age of 25 last year were jobless or underemployed, the highest share in at least 11 years. In 2000, the share was at a low of 41 percent, before the dot-com bust erased job gains for college graduates in the telecommunications and IT fields.