Tax reforms usually change both tax rates and tax bases. Using a panel of income tax returns spanning the two major U.S. tax reforms of the 1980s and a number of smaller tax law changes, I find that the elasticity of income reported on personal income tax returns depends on the available...

In theory, the U.S. tax system aims to attribute and tax all business income to individuals. But the tax treatment of this income varies. Pass-through income is taxed when earned; capital-gains income is taxed when realized; dividends when distributed; other forms of business income may escape...

Existing tax bases, though, depend on a broader range of information about each individual than just labor income. In principle, this supplementary information can help in designing a tax that has more attractive distributional properties, by more closely approximating an ability tax. The...