Vermont officials say changes in federal tax law could make it more difficult to estimate how much money will be flowing into the state treasury this year.

Lawmakers and the governor rely on revenue projections to know how much they'll have to spend.

Vermont Public Radio reports the forecasts are always imprecise, but a provision in the new federal tax law that will allow for increased deductions on income generated from businesses could make that even harder.

Commissioner of Taxes Kaj (Kie) Samsom says the 20 percent business income deduction could prompt people to change the way they do business.

If says if some businesses use some accounting maneuvers to take advantage of the new deduction, state revenues could be reduced.