Americans keep getting better at paying their credit card bills on time, according to the results of a new Experian study. Researchers reported that the dollar amount of bank credit card accounts over sixty days delinquent fell 21 percent in July 2012 from the same period a year earlier. Auto loan and mortgage delinquencies also dropped significantly over the past year, researchers said. Equifax Chief Economist Amy Crews Cutts told reporters that consumers have been making monthly payments on time, while qualifying for home refinancing deals in larger numbers during the survey period. Equifax's figures also suggest that more Americans have been paying more than the required minimum monthly payments on their credit cards, resting more of their available credit. Experian's numbers mirror similar reports from credit reporting agency TransUnion and credit card issuer Capital One. TransUnion's Ezra Becker called the current credit card delinquency rate the lowest in 18 years, despite measuring a modest increase in the average credit card debt per borrower between 2011 and 2012 (today's estimate: $4,971).