Total non-revolving debt was $2.8 billion on July 31, up 6% from a year earlier. Non-revolving debt rose 14.4% to $357.6 billion among credit unions, and 3.9% to $695.4 billion among banks.

The resulting increase in credit union's share was amplified by a major revision that reduced reported levels of finance company credit card debt by more than half and non-revolving debt by 18% for months stretching back to December 2015.

The revisions were only minor for credit unions and banks, with levels changing less than 0.2 percentage points and only for recent months. However, the changes among finance companies reduced total consumer debt for the prior 18 months by about 3%.

Credit unions' 5.64% share of card debt was up 5 basis points from June, and 10 basis points from July 2016. The revisions added about 5 basis points to credit unions' share. Banks' share of credit cards was 86.10% in July, down from 86.65% in July 2016.

Credit unions' share of non-revolving debt was 12.98% in July, their highest share since September 2007. It was up 18 basis points from June and 23 basis points from July 2016. Banks had a 25.24% share, up 1 basis point from June and down 51 basis points from a year ago.

Credit unions have been increasing their share of credit cards since the end of the recession with more sophisticated offerings. Federally insured credit unions held $53.1 billion in credit card debt as of June 30, up 17% from a year earlier, according to NCUA data.

Of that $4.1 billion increase, 46% came from Navy Federal Credit Union of Vienna, Va. ($82 billion in assets, 7.2 million members), which last week announced that it had reached a deal to offer a rewards card through American Express.

Navy Federal launched the More Rewards Card now to allow members to use it during the holidays. It rewards triple points at supermarkets and gas stations, double points at restaurants and 1 point on everything else.

"You have to buy groceries, you're going to get gas and go out to eat—now you can also benefit from earning additional points when you do," said Matt Freeman, Navy Federal's head of credit card products.

Navy Federal, which had $13.1 billion in credit card debt, and the five next-largest holders of credit cards accounted for 33% of credit unions' credit card balances and 55% of the increase in the 12 months ending June 30. The other five are:

• Pentagon Federal Credit Union of Alexandria, Va. ($22.8 billion in assets, 1.6 million members) with $1.7 billion in credit card debt, up 4.8%.
• BECU of Seattle, ($17.2 billion in assets, 1 million members) with $995.1 million in credit card debt, up 10.2%.
• State Employees' Credit Union of Raleigh, N.C. ($36.9 billion in assets, 2.2 million members) with $691.8 million in credit card debt, up 13.4%.
• SchoolsFirst Federal Credit Union of Santa Ana, Calif. ($13.9 billion in assets, 759,177 members) with $674.1 million in credit card debt, up 8.7%.
• Pennsylvania State Employees of Harrisburg, Pa. ($5 billion in assets, 432,398 members) with $658 million in credit card debt, up 7.9%.

Because of revisions earlier this year, the national peaks for credit card debt reverted to the Decembers of 2007 and 2008, when the nation was sliding into recession. Those are the only two months with total U.S. credit card debt topping $1 trillion.

A report from Wells Fargo says that record could be topped by early 2018.