American consumers racked up $34.4 billion in credit card debt during the second quarter, representing the largest second-quarter accumulation since at least 1986, and are on track to rack up $1 trillion by the year’s end, the personal finance website WalletHub said today.

In its 2016 Credit Card Debt Study, the personal finance site called the figures “serious cause for concern” and drew comparisons between this year’s second quarter and the same period in 2007, when Americans accumulated $31.9 billion in credit card debt. Year-to-date, Americans accumulated $912 billion in credit card debt, while by this time in 2007, they had accumulated $898 billion.

In the second quarter this year, the charge-off rate stood at 3.13 percent, compared with 3.85 percent in the second quarter of 2007.

Finally, the personal finance site noted that last year saw a record increase in credit card debt, of $71 billion, and last quarter saw a record-low first-quarter pay down of $27.5 billion.

WalletHub also recently ranked several major credit card issuers by transparency. The site named Capital One, Bank of America, U.S. Bank, State Employees Credit Union, Boeing Employees Credit Union, Pentagon Federal Credit Union and Navy Federal Credit Union as having the clearest overall credit card applications. It named Wells Fargo and San Diego County Credit Union as having the least clear credit card applications.