NIT picking: The macroeconomic effects of a Negative Income Tax

I study a revenue-neutral reform of the U.S. income tax and welfare system that involves the adoption of a Negative Income Tax (NIT). The reform is undertaken in a life-cycle economy with individual heterogeneity and uninsurable idiosyncratic labor risk. The optimal NIT consists of a 22% rate and a transfer equivalent to 11% of per-capita GDP. The ex-ante average welfare gain is a 2.1% annual increase of individual consumption. I show that a NIT outperforms a flat tax reform (income tax plus deduction) by a considerable margin. The key consequence of the reform is that high-productivity agents increase their relative importance in the labor supply at the expense of low-productivity agents.