Hawai'i credit card holders led the nation in the amount of debt they took on during the third quarter, though they did so without increasing their delinquency rate, according to a new study.

TransUnion LLC, one of the nation's biggest credit agencies, said Hawai'i residents had the steepest increase in average credit card debt over the previous quarter, adding 5.48 percent.

Average credit card debt per borrower rose to $6,002, the 10th highest in the nation, TransUnion said in an e-mail.

The increase is notable because it comes at a time of change in the credit card business because of the passage of the Credit Card Accountability Responsibility and Disclosure Act, the first phase of which went into effect in August. The act is targeted at ending credit card issuer abuses, but some observers say it may have unintended effects that could result in higher costs for some card holders.

TransUnion noted nationally there was a decline in credit card average debt along with falling delinquency rates that were perhaps in response to some banks changing rules. The second phase of the credit card law takes effect in February and limits banks' ability to raise interest rates on existing balances, among other changes.

"Many lending institutions modified credit card rules, fees and charges in the third quarter in advance of the credit card act taking effect in February 2010," said Ezra Becker, TransUnion financial services group director of consulting and strategy.

Nationally, average credit card borrower debt fell by 1.87 percent compared to the second quarter. The average debt nationally was $5,612.

"The national savings rate fell in the third quarter, possibly indicating continued consumer efforts to keep debt to a minimum and debt repayment under control in the face of an already depressed labor market," Becker said in a press statement.

He said it was the first time in 10 years that third-quarter national delinquency rates had shown a decline from the prior quarter.

Hawai'i was in step with this trend, with delinquency rates, or the percentage of bankcard borrowers who are 90 days or more delinquent on one or more of their credit cards falling to 0.89 percent, or 0.02 percentage points less than in the second quarter.

Nationally the delinquency rate declined to 1.1 percent.

TransUnion culled the report from about 27 million randomly sampled, but anonymous credit card files during the July to September quarter. It represented about 10 percent of active credit users in the U.S.

Other figures released by TransUnion show:

• Hawai'i's delinquency rate rose when examined over a one-year period. TransUnion reported the delinquency rose to 0.89 from 0.87 percent in the third quarter of 2008.

• Hawai'i ranked 40th out of all states and the District of Columbia in delinquencies.

• The state with the highest delinquency was Nevada at 1.98 percent and was followed by Florida (1.47 percent) and Arizona (1.35 percent).

• North Dakota led the nation with the lowest delinquencies at 0.66 percent. South Dakota was second at 0.70 percent, just ahead of Alaska at 0.73 percent.

• Alaska had the highest average credit card debt at $7,699. Iowa had the lowest at $4,225.