Washington, D.C. ? About 57 percent of students at 16 for-profit colleges who started classes in the 2008-2009 academic year have dropped out, Sen. Tom Harkin, D-Iowa, said Thursday.

During the three years, an estimated 1.9 million students left the institutions, most with nothing to show for their time except debt, Harkin said today at a hearing in Washington, quoting from a report by his office. The Senate Health, Education, Labor and Pensions Committee held a hearing Thursday into whether the schools misled students on employment prospects after graduation.