Nearly 350 of more than 1,500 accredited four-year colleges in the U.S. have a lower graduation rate or higher student-loan default rate than four-year colleges that lost their accreditation since 2000. Colleges that were dropped by accreditors had an average graduation rate of 35% and an average student-loan default rate of 9.3%.
http://graphics.wsj.com/accredit-2015/