The effect of taxes on corporate financing decisions: Evidence from a panel of Italian firms

This paper provides additional evidence on the relationship between corporate taxes and debt using panel data on Italian companies. The panel covers 1054 companies for the years 1982-1994. The paper follows the Graham-Shevlin methodology for calculating company specific marginal tax rates (MTR) relying on the non-linearity of corporate tax schedules resulting from company losses and the ensuing tax provisions (carry-forward and backward rules). In the period covered by the panel there were in Italy two taxes on corporate income (IRPEG and ILOR), with different loss carry-forward rules, whose statutory tax rates and tax bases changed several times. For these reasons the simulated MTRs display both cross-sectional and time-series variation. The paper tests whether taxes encourage the use of debt by analysing incremental financing decisions. In order to cope with the endogeneity of the MTR the paper considers two different specifications. The first uses the lagged value of the simulated MTR. The second employs the estimate of before-financing MTR proposed by Graham et al. (1998). Significant cross-sectional tax effects are identified under both specifications whereas time-series variation cannot be identified if due account is taken of firm-fixed tax effects. The paper also investigates whether personal taxes affect corporate financing decisions. The MTR may either overstate or understate the fiscal benefit of debt financing according to whether, at the personal level, interest income is taxed at a rate that is higher or lower than the tax rate on returns from common stocks. Differences in the dividend-payout ratio across companies and several reforms in interest, dividend and capital gains taxation provide sufficient cross-section and time-series variations to identify the effect of personal taxes on debt usage.