We assess the business provisions of the 2017 Tax Cuts and Jobs Act, the biggest corporate tax
cut in US history. We draw five lessons. First, corporate tax revenue fell by 40 percent due to the
lower rate and more generous expensing. Second, firms with larger declines in their effective tax
wedge increased investment relatively more. In aggregate, we suggest a loose consensus from the
literature that total tangible corporate investment increased by 11 percent. Third, the business tax
provisions increased economic growth and wages by less than advertised by the Act’s
proponents, with long-run GDP higher by less than 1% and labor income by less than $1,000 per
employee. Fourth, provisions that increase foreign investment by US-based multinationals also
boost their domestic operations. Fifth, some of the expired and expiring provisions, such as
accelerated depreciation, generate more investment per dollar of tax revenue than others.