Steven Mnuchin, President-elect Trump’s pick for Treasury secretary, said Thursday that he thinks tax reform should be deficit-neutral.

“I think we want to make sure that tax reform doesn’t increase the size of the deficit,” Mnuchin said during his confirmation hearing.

Still, Mnuchin noted that the administration believes in “dynamic scoring,” which factors economic growth into cost estimates. The tax reform plan Trump released in September was estimated by outside groups to cost trillions of dollars, even under dynamic scoring.

House Republicans and Senate Majority Leader Mitch McConnell (R-Ky.) have also said they want tax reform to be revenue-neutral.

{mosads}A revenue-neutral bill may be easier to pass. If Congress wants to pass a tax reform bill through budget reconciliation, which would prevent the Senate from being able to filibuster it, the bill can’t increase the deficit outside of the 10-year budget window.

Mnuchin said that the campaign had to rely on outside estimates because its staff size was “modest.” The campaign agreed with some of the assumptions made by outside groups but disagreed with others, he said.