Valuation of the debt tax shield

In this study, we use cross-sectional regressions to estimate the value of the debt tax shield. Recognizing that debt is correlated with the value of operations along nontax dimensions, we estimate reverse regressions in which we regress future profitability on firm value and debt rather than regressing firm value on debt and profitability. Reversing the regressions mitigates bias and facilitates the use of market information to control for differences in risk and expected growth. Our estimated value for the debt tax shield is approximately 40 percent (10 percent) of debt balances (firm value), net of the personal tax disadvantage of debt.