First-quarter net income for BOK Financial Corp. was down 11.6 percent from the same time a year ago, the Tulsa company reported Wednesday.

The regional financial services provider stated earnings of $55.0 million, or 81 cents per diluted share, compared with $62.3 million, 92 cents a share, for the first three months of 2008.

A one-time after-tax gain related in part to the sale of Visa Inc. Class B common stock helped boost BOK's net income in last year's first quarter.

"BOK Financial is pleased to report a strong start to 2009 as we continue to manage the challenges of the current recession," President and CEO Stan Lybarger stated in a written comment. "Our solid capital and liquidity positions and diverse revenue sources have allowed us to perform much better than the industry as a whole."

Steven Nell, the company's chief financial officer, said in a phone interview that the first-quarter earnings outcome was good, given the slowdown in the national economy and the markets that BOK Financial serves.

The biggest difference between this quarter and the same quarter last year is loan loss expenses, which reflects the recession, Nell said. Provision for credit losses was $45 million for the quarter compared with about $18 million a year ago.

The company's core operating income, before credit losses, has remained strong. Nell pointed out that pre-tax net operating income was $123.6 million for the first quarter, up from $109.3 million for the 2008 first quarter.

Pre-tax net operating income is often used as a measure of a company's ability to generate earnings and absorb credit and other losses.

Net interest revenue grew to $169.8 million for the quarter, up from $147.1 million last year. After provision for credit losses, net interest revenue totaled $124.8 million.

The company's fees and commissions revenue totaled $121.5 million, up from $113.9 million in the year-earlier period.

As Lybarger's noted at Tuesday's annual shareholders meeting, BOK Financial's diverse fee revenues differentiates it from other regional banks. The bank holding company earns more revenue from fees than do many other financial institutions its size.

Mortgage banking revenue rose to $18.5 million for the quarter from $8 million a year ago.

"Our mortgage banking revenue was very strong in the first quarter," Nell said.