"We're in the risk business," he said. "Anyone who says they don't have any delinquencies is not doing their job."

Among all credit unions, business loan portfolios were $66.6 billion at the end of 2016, including unfunded commitments, up 15% from the end of 2015. It was the strongest growth since 2008, according to NAFCU.

Callahan & Associates, a credit union consulting firm in Washington, tracked business loans granted or purchased at $21.6 billion in 2016. Production grew 15% in 2016, the fastest growth since 2012.

Callahan also ranked credit unions by their Member Business Loan portfolios.

At the top for 2016 was Melrose Credit Union of New York City, a superlative that it can carve on its tombstone after being taken into conservatorship by the NCUA in February.

Melrose's distinction was a large part of its problem. Its $1.6 billion in member business loans on Dec. 31, 2016 accounted for a whopping 89% of total loans. And its business loans were mainly for an archaic New York City institution: The taxi medallion, a sort-of public franchise created in 1937 to control unbridled competition. During the Great Depression, some taxi drivers were working 20-hour shifts and still were not able to support their families.

There were 12,000 medallions then, and there were still only 13,000 by 2015, making each a valuable commodity. Now they are remarkably less valuable as fewer riders wave toward the street and more are tapping into riding-sharing apps on their phones. Uber and its ilk sent Melrose under.

Melrose was thus not part of the eight credit unions contacted for this story, but the next largest were contacted: BECU of Seattle ($840 million, up 59%) and DCU ($833 million, up 20%).

The other six contacted were: Alliant Credit Union of Chicago ($356 million, up 24%); Redwood Credit Union of Santa Rosa, Calif. ($322 million, up 20%); Dupaco Community Credit Union of Dubuque, Iowa ($285 million, up 10%); Jeanne D'Arc Credit Union of Lowell, Mass. ($216 million, up 44%); Wright-Patt Credit Union of Dayton, Ohio ($132 million, up 50% and Redstone Federal Credit Union of Huntsville, Ala. ($82 million, up 18%).

The eight credit unions represented 5% of member business loan portfolios at the end of 2016. Their portfolios grew twice as fast over the year, and their loan production growth was also significantly greater.

The group's loan portfolios reached $3.1 billion by year's end, up 31% from the end of 2015. Loans granted or purchased were $1.4 billion, up 24% from 2015.

In the Northwest, BECU ($16.4 billion in assets, 1,000,944 members) generated $408 million in business loans in 2016, up from $243 million in 2015.

Dana Gray, BECU's vice president of business and wealth services, said BECU was fortunate to have low exposure to business lending during the recession. The program began in 2004, but was inactive by 2008.

In 2012, BECU began a five-year plan to reinvest in business services. The division hired business specialists and business relations managers. The credit union also expanded into the Spokane market in eastern Washington.

The credit union's investment, trust and mortgage teams work together to generate leads, Gray said.

"We have purposefully moved away from strictly transactional lending to relationship lending," she said. "We began to see very strong results."

The Northwest real estate market is one of the strongest in the nation. Commercial rents are rising, vacancies are low. Appraisals continue to come in high.

Conditions are so good, Gray has started to slowly tighten lending criteria.

"Never for a moment do we take this market for granted," she said. "Now is the time to look ahead and prepare for lower levels of real estate activity."

In New England, DCU's business loan volume was $327 million in 2016, up 37% from 2015.

"We had our best year ever. I would expect about the same in 2017," said Stephen K. J. Mackowitz, SVP of commercial lending at DCU ($7.6 billion in assets, 623,265 members). "The Boston area has been a hot market in the last few years."

Mackowitz, who started working in banking in the 1970s, joined DCU in 2002 to start the credit union's business lending program.

He had connections, and tried to hire people who also knew how to make them for DCU. "They're out knocking on doors and building relationships."

About three quarters of the credit union's business comes from existing customers who expand their business with the credit union by opening accounts, getting credit cards or taking out additional loans.

"They trust us and come back," he said.

Wright-Patt ($3.5 billion in assets, 332,205 members) generated $101 million in business loans in 2016, up from $40 million in 2015, based on the credit union's Call Reports.

Business loans were 5% of total loans at the end of 2016.

Scott R. Everett, Wright-Patt's vice president of member business services, said the credit union counts its loans differently, but the trend is the same: Up.

"At this point we have the luxury of saying no as much as yes," Everett said. "We're trying to grow the business, but we're trying to do it in a more prudent manner."

The credit union has been trying to lower costs and increase its rate of applications to closures by using a scoring model on small loans. It allows lenders in the branches to enter key data that can be used to give potential borrowers a quick answer on whether the credit union can lend them money.

The scoring model is generally used on loans up to about $80,000, he said.

At Redstone in Alabama, business loans account for only 5% of total loans.

"We're trying to increase that," John N. Cook, vice president of lending at Redstone ($4.7 billion in assets, 390,985 members), said.

Redstone's business lending has been counter-cyclical.

"As the economy fell off the cliff, the competition in the business space changed dramatically," Cook said. Banks, which had often snatched loans faster than the credit union could close them, "just disappeared."

After that, he said, "If we approved it, it was as good as booked."

But by 2012, "the banks came roaring back," he said, and Redstone's volume declined for two years. The last two years have shown growth, in large part because Redstone shifted its strategy to focus on smaller businesses that banks tended to ignore.

And with these smaller businesses, Redstone sought to provide more coaching so that they would apply for loans only when they were ready and likely to be approved. If they weren't ready, Redstone managers could send them to small business advisors in the community to hone their business plans.

Like others, it is also speeding its approval process by using a scoring model for smaller loans.

Later this year, Redstone will further expand in middle Tennessee as it opens a new branch in Murfreesboro, allowing its business loan portfolio to further expand, Cook said.

"If all goes well, we could move it as high at $100,000 this year," he said.

At Dupaco Community Credit Union in Iowa, business loans account for 32% of its total loans – a figure possible under member business lending restrictions because its program began in the 1980s, allowing Dupaco ($1.5 billion in assets, 95,992 members) to be excused from business lending caps.

Andrew Katrichis, Dupaco's SVP of business lending and operations and a lender for more than 30 years, said credit unions ramping up their business lending should build slowly, build carefully and concentrate on each new member.

"It's not just about interest rates and terms," Katrichis said. "It's about relationships and trust building. If you lose sight of that, and treat them like a number, you'll be losing members all day long."