Late last year, total student debt outstanding surpassed $1 trillion for the first time. Now, the problem of student loan delinquency is generating its own eye-popping numbers.

New data released today shows 11% of student loans were 90 days or more past due in the third quarter, up from 8.9% in the previous quarter and 8.8% a year prior, according to the Federal Reserve Bank of New York. It’s also the highest since at least 2003, when the bank first started tracking student loan delinquencies. “It’s a red flag and a warning sign that more Americans are struggling to repay their student loans — things are bad, really bad, and getting worse,” says Rich Williams, higher-education advocate at the U.S. Public Interest Research Group, a nonprofit based in Washington.

The latest data comes at a time when delinquencies on many other consumer debts, including credit cards and mortgages, are dropping. Overall, delinquency rates on outstanding consumer debt fell to 8.9% in the third quarter, from 10% a year prior, according to the FRBNY.