Ways and Means Chairman Kevin Brady on Friday released a substitute amendment, or chairman’s mark, to the tax overhaul bill his panel will begin to markup on Monday, but said he plans to offer an another, more substantive amendment at the start of the markup.

The change, designed to conform the bill with the budget instruction, would require provisions that are indexed to inflation use the chained Consumer Price Index starting immediately rather than after five years of enactment. 

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Chained CPI costs less than the regular Consumer Price indexing, meaning the acceleration of its use in the tax overhaul should add some additional revenue to the budget score. 

According to the Committee for a Responsible Federal Budget, regular CPI overstates inflation because it fails to account for the fact that when prices of similar goods change, consumers often switch to the cheaper option. Chained CPI recognizes that and more accurately ensures value keeps pace with inflation, CRFB says. 

The other change meant to conform with the Senate rules would eliminate a provision included in the original bill that would have prevented tax treaty benefits from being applied to deductible payments made to U.S. subsidiaries from their foreign parent corporations that would not have otherwise qualified for the treaty benefits. 

This provision would not comply with the Senate’s Byrd rule because the Foreign Relations Committee, which has jurisdiction over tax treaties, did not receive a reconciliation instruction.

Niels Lesniewski contributed to this report.