https://www.cnbc.com/2017/12/11/treasury-department-report-says-gop-tax-cuts-will-pay-for-themselves.html
"The Treasury Department on Monday estimated that Republican tax cuts will pay for themselves through growth — but it assumes other policy changes that have not yet happened will take place.
In a one-page analysis, the agency projected that the tax plan as passed by the Senate Finance Committee would boost the real GDP growth rate to 2.9 percent over 10 years, up from a previous 2.2 percent assumption. That growth would lead to a $1.8 trillion increase in tax revenues — more than enough to cancel out the $1.5 trillion in revenue lost from the tax cuts, the Treasury says.
The Trump administration estimate is more optimistic than others that have modeled potential growth and revenue. The congressional scorekeeper, the Joint Committee on Taxation, has estimated that the same Senate plan would increase deficits by more than $1 trillion over a decade, even after a modest growth increase is taken into account."
Looks like the 3rd paragraph is the most accurate so far.