Estimating taxable income responses using Danish tax reforms

This paper estimates taxable income responses using a series of Danish tax reforms and population-wide administrative data since 1980. The tax variation and data in Denmark makes it possible to overcome the biases from nontax changes in inequality and mean reversion that plague the existing literature. We provide compelling graphical evidence of taxable income responses, arguably representing the first nonparametrically identified evidence of taxable income elasticities using tax reforms. We also present panel regression evidence that is extremely robust to specification, unlike previous results which have been very sensitive.