The Treasury Department's analysis of the Senate's version of the Tax Cuts and Jobs Act, which cites Trump administration estimates of 2.9% real GDP growth over 10 years included in its 2018 budget, projects an increase in tax revenues of $1.8 trillion during a 10-year window.
"Adding this $1.8 trillion of incremental revenue to the static current law score of -$1.5 trillion results in total receipts over the 10-year window increasing by $300 billion," the memo reads. "These increased receipts are primarily collected in the last five years, as full expensing creates growth in early years but results in a deferral of collection of taxes."
A Joint Committee on Taxation analysis of the version of the Tax Cuts and Jobs Act debated in the Senate Finance Committee predicted that GDP would increase by 0.8% over a 10-year budget window while adding an additional $1 trillion to the U.S. fiscal deficit.
"[JCT] estimated $408 billion of additional tax revenue. Adding this $408 billion to the static score leads to a change in total projected receipts under JCT's assumptions of approximately -$1 trillion on a current law basis," the Treasury memo reads. "OTP compared this 2.9% GDP growth scenario to a baseline of previous projections of 2.2% GDP growth. Treasury expects approximately half of this 0.7% increase in growth to come from changes to corporate taxation."
The department's memo noted that neither JCT nor Treasury released a plan showing increased tax receipts under the House plan, but Treasury "would not expect the results to be materially different."
A House-Senate conference committee is scheduled to meet publicly on Dec. 13 as it begins the process of merging the differing versions of the tax reform packages passed by both chambers.