Are corporate tax rates, or countries, converging?

The statutory rate and effective tax rate imposed on corporation income—as well as the dispersion of these rates—began to decline in the 1980s. Is this due to changes in the domestic determinants of corporate taxation or increases in international pressures for tax competition?This paper finds clear evidence that the corporate tax rate is insulated from a country's revenue needs: across countries, there is no association of the expenditure-GDP ratio with the corporate statutory rate and only weak evidence of a positive association with the average rate. There is suggestive, but not definitive, evidence that the domestic role of the corporate tax as a backstop to the individual income tax is important: across countries, there is indeed a strong association between the top individual rate and the top statutory corporate rate.There is intriguing evidence about the role of international competitive pressures on corporate taxation. Measures of openness are negatively associated with statutory corporate rates, although not with revenues collected as a fraction of GDP. Strikingly, larger, more trade-intensive countries do collect more corporate tax, but this may be because these countries are more attractive venues for investment.