To our knowledge, this paper provides the most comprehensive analysis of firm-level corporate income tax expenses to date. We use publicly available financial statement information to estimate firm-level effective tax rates (ETRs) for 10,642 corporations from 85 countries from 1988 to 2007. We...

We find that employee stock option deductions lead to large aggregate tax savings for Nasdaq 100 and Samp;P 100 firms and also affect corporate marginal tax rates. For Nasdaq firms, the median marginal tax rate is 31 percent when option deductions are ignored but falls to 5 percent when one...