At this point, it’s not breaking news to say that Americans are crushed under trillions in student debt, but a new study from the Brookings Institute breaks down who owes what. The findings point to some surprising culprits for the crisis: the small balances from community and for-profit colleges.

While students at those schools accumulate less individual debt than students at four-year universities, they default on their loans in much greater numbers. Since 2011, more than 20 percent defaulted within two years — twice the rate of four-year university borrowers.

Here’s a breakdown of colleges with the most student debt. That outbreak of yellow on the right? The rise of non-four-year debts:

Who's paying?

“[These students] borrowed substantial amounts to attend institutions with low completion rates and, after enrollment, experienced poor labor market outcomes that made their debt burdens difficult to sustain,” the researchers write. The average for-profit borrower who left school in 2011 and got a job in 2013 probably earned about $20,900. But fully 21 percent were not employable. Community college borrowers pulled in an average of $23,900 — but one in six still couldn’t find work.

All of which adds up to the well-deserved disintegration of for-profit colleges. They’re rotting from the inside, dying from a toxic stew of third-rate courses, inflated pricing, and predatory lending to low-income students, who are wising up to the scheme. This year the University of Phoenix lost half its students, and the stock price of its owner, Apollo Education Group, started a collapse from which it has yet to recover. In the past three months, the stock has fallen by a third, according to The American Trade Journal. Year-to-date, the stock’s total performance has plunged by two-thirds. Apollo Education Group’s media line has yet to respond to an Inverse interview request as to why they think students are fleeing, but some insight could be found in the reviews behind the college’s single-star rating on Consumer Affairs. They read like the mournful wails of a crypt’s worth of damned credit scores bludgeoned by shady billing practices. The bills are coming due, and students aren’t the only ones paying up.

Photos via Brookings, Getty