12/16/2013 01:16 EST | Updated 02/15/2014 05:59 EST

56 per cent of students who started college in 2007 have graduated, underscoring challenges

WASHINGTON - Only 4 in 10 students who entered college in 2007 have earned degrees from the school where they started.

That's according to a review released Monday from the research arm of the National Student Clearinghouse, a non-profit organization that works with colleges to verify students' enrolment and graduation status. More than 3,500 schools co-operated with the review.

Overall, 56 per cent of those who started college in 2007 have finished their coursework on any campus. About 29 per cent of those who started college that year are no longer taking classes toward a degree.

Graduation rates are one piece of the U.S. Department of Education's still-emerging college rating system. The Education Department wants to pressure colleges to keep costs down and perhaps link federal financial aid to their performances.