Trump’s two flagship US corporate tax reforms are a reduction in the federal corporate income tax rate to 15%, from 35% and a one-off 10% tax rate on profits repatriated to the US.

It is claimed that the current 35% corporate income tax rate makes domestic investment by US companies unattractive and that they therefore invest preferentially outside the US. Cutting it to 15% is aimed at reversing this, by providing a greater incentive to invest in the US.

To further boost this, Trump also proposes a 100% tax write-off of the cost of investment in new plant and machinery, though at the price of foregoing a tax-deduction for interest.