 Wallet Hub, which tracks credit card spending, estimates that Americans are now carrying a balance of more than $1.25 trillion on their cards. For those who pay their balance in full every month, that's merely a convenience. For others, it's a costly form of debt. The average interest rate on balances carried over from month to month is nearly 23%. A NerdWallet survey finds nearly one out of four credit card users are stressed about their outstanding debt. 46% are still paying off bills they racked up last summer. Scott Horsley, NPR News, Washington.