Callahan & Associates, which held its quarterly Trendwatch webinar Wednesday, said its analysts found that the growth was came from a much broader source than the fast-growing indirect auto lending channel. Membership growth over the past 12 months would have fallen to 3.8% without members gained through indirect loans.

Credit unions loan portfolios grew 10.9% in the 12 months ending June 30, compared with 3.7% for banks. Deposits grew 8.2% at credit unions and 4.6% at banks. However, the average bank had $2.9 billion in assets, compared with $236 million for the average credit union. And return on assets (after taxes) was 1.09% for banks, compared with 0.77% for credit unions in the second quarter, according to Callahan.

The faster growth sent credit unions' second-quarter market shares rising. Callahan found credit unions' share of auto loans was 18.9%, up from 17.5% a year earlier and 15% in 2012. They had 5.4% of credit card balances, up from 5.3% a year ago. Their mortgage originations were 8.2% of the market, up from 7.3%.

Rick, of CUNA Mutual, stuck with his forecast from last month that GDP will rise 2.3% this year and next. "This will boost wages, consumer confidence and ultimately keep credit union lending growth strong into 2018," he wrote.

The gains among credit unions come as new car sales decline, and home sales are constrained by a limited supply. The Core Logic Home Price Index in June was 6.7% higher than a year earlier, and the July index is expected to break its record high set in April 2006. Home prices are expected to rise another 5% in 2018.

"The return of first-time homebuyer sales could herald stronger demand for home purchases in coming years," CUNA Mutual reported. "Credit union mortgage lending should increase as improving financial positions among borrowers and rising incomes justify loosening credit standards. In addition, confidence in the housing market is rising as the general economy strengthens and lingering memories of the most recent housing downturn fade from view."

Callahan said rising interest rates have driven purchasers to adjustable-rate loans. Fixed-rate mortgages accounted for 65.6% of second-quarter originations, down 3 percentage points from a year ago, while balloon mortgages rose to 22.9% — twice their share three years earlier.

Callahan also reported that loan originations for the first half were $240.3 billion, up 10% from 2016's first half. This included:

• Cars and other consumer loans, up 9.3% to $143.6 billion
• First mortgages, up 7.4% to $67.5 billion.
• Other real estate loans, up 17% to $16.2 billion
• Member business loans, up $26.3% to $13 billion.