Redwood Credit Union, Sonoma County's second-largest financial institution, saw its assets grow 9 percent last year to $2.1 billion, even as problem loans continued to decline.

In year-end results reported to federal regulators, the Santa Rosa credit union said membership increased 6 percent last year to 224,000 people. Deposits grew 10 percent to $1.9 billion.

"We're seeing some huge improvements in a lot of areas," Brett Martinez, the credit union's president and CEO, said Monday.

Net income doubled last year to $32 million. Martinez said the $17 million jump was linked to two sources unrelated to deposits: a $4 million rise in non-interest income and fees, and a $15 million decline in the amount that Redwood must set aside for future loan losses.

The non-interest income and fees came from the credit union's full-service investment division and from its own insurance company and auto dealership, Martinez said.

As a credit union, Redwood is a nonprofit owned by its members that provides loans and other financial services to members. Its dollar assets rank behind only Luther Burbank Savings among county-based financial institutions that serve the general public.

Redwood's full-time workforce grew 6 percent last year to 387 employees.

The 2012 results show "our members are doing better," Martinez said.

In the recession, members lost jobs, received pay cuts and experienced drops in business income, Martinez said. Since then, many have taken steps to better manage their finances and to refinance mortgages at lower rates.

Such efforts helped the credit union reduce its delinquent loans by 62 percent last year to $13 million.

With fewer problem loans, Redwood has been able to steadily reduce the amount of money it must set aside to cover loan losses. The company, which reserved $48 million for loan losses in 2009, lowered that figure to $11.7 million last year, a decline of 56 percent from 2011.

In 2012, Redwood's total loan portfolio increased 4 percent to $1.5 billion. The credit union made 26 Small Business Administration loans, the most of any North Bay lender, Martinez said.

Founded in 1950 to serve Sonoma County government employees, Redwood became the 11th largest credit union in California last year. It operates 18 branches in Sonoma, Mendocino, Napa, Marin and San Francisco counties.

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