U.S. credit card users are getting better about submitting their payments in a more timely manner, even as banks increasingly are issuing cards to borrowers with imperfect credit. The rate of payments 90 days or more overdue dipped in the first quarter to 0.73 percent, TransUnion reports, down from 0.78 percent in the fourth quarter of 2011 and 0.74 percent in the first quarter of 2011. While late payments are trending downward, cardholders are amassing more debt. The average credit card balance in the first three months of the year was $4,692 -- a jump of 6.1 percent from the same period of last year. Some of that shift may be explained by the cardholders themselves, as nearly a fourth of new cards issued in the 2012 first quarter went to higher-risk consumers. "We expect these consumers have been making active use of their cards, because in many cases they may not have had access to cards in the past couple of years," explains TransUnion's Charlie Wise.