North Dakota's corporate tax collections have not kept pace with the state's economic growth, and a more aggressive audit program is needed, the Democratic candidate for state tax commissioner says.

"This, to me, is counterintuitive, that we've seen economic growth, and we've seen economic development, and yet we have corporate tax (collections) that are lagging behind," Brent Edison said Tuesday.

At the same time, North Dakota's sales and individual income tax collections have risen steadily, and property taxes collected by local governments have gone up, he said.

Cory Fong, the incumbent Republican tax commissioner, said corporate tax collections have rebounded strongly in the past two years. Audits sometimes bring in corporate tax collections years after the taxes were assessed, which causes the number to fluctuate, he said.

North Dakota's corporate income tax collections have bounced around in the last decade. They totaled $49 million during the 1996 budget year, and rose to $65.5 million two years later, Tax Department data show.

The low point was the 2004 budget year, in which the state collected $40.2 million. The fiscal year for North Dakota state government runs from July 1 through June 30.

Corporate tax collections jumped to $62.7 million in 2005, and have already surpassed that during the 2006 budget year, which ends June 30. In the first 10 months of the budget period, the state has collected $86.1 million in corporate income taxes, the state budget office says.

"It's a spectacular number," Fong said. "The time period that Mr. Edison is looking at … he totally excludes these last two years, which I think are very compelling and important."

Fong has been tax commissioner since June 2005. Gov. John Hoeven appointed him to succeed Rick Clayburgh, who resigned to become director of the North Dakota Bankers Association. Fong is running his first statewide campaign this year.

Edison said a stepped-up program of corporate tax auditing is needed to ensure out-of-state companies are paying their "fair share" of taxes. U.S. Sens. Byron Dorgan and Kent Conrad, both of whom are former state tax commissioners, ran similar programs, and Republican tax officials have considered them less important, Edison said.

If the Tax Department cannot reallocate its employee time to put more emphasis on corporate tax audits, he will ask the Legislature for additional personnel, Edison said. He believes the expenditure would more than pay for itself in added collections.

"I would say we need some investment here in the area of compliance when it comes to out-of-state corporations," he said.

Fong said corporate tax enforcement is already a priority in the agency, and an ongoing revamping of its computer system will make it easier. Technology and the Internet has already made audit information more readily available, he said.

"Our auditing methods have changed," he said. "We don't need to have, for example, auditors traveling the country, and spending a lot of state resources to do that."