About 1.5 million, or 53.6 percent, of bachelor’s degree-holders under the age of 25 last year were jobless or underemployed. Out of the 1.5 million who languished in the job market, about half were underemployed, an increase from the previous year. According to the Census, the number of Americans under the age of 25 with at least a bachelor’s degree has grown 38 percent since 2000.