We estimate firm-specific marginal cost of debt functions for a large panel of companies between 1980 and 2007. The marginal cost curves are identified by exogenous variation in the marginal tax benefits of debt. The location of a given company's cost of debt function varies with characteristics...

We study optimal capital structure by first estimating firm-specific cost and benefit functions for debt. The benefit functions are downward sloping reflecting that the incremental value of debt declines as more debt is used. The cost functions are upward sloping, reflecting the rising costs...

We estimate firm-specific marginal cost of debt functions for a large panel of companies between 1980 and 2007. The marginal cost curves are identified by exogenous variation in the marginal tax benefits of debt. The location of a given company's cost of debt function varies with characteristics...

The authors provide a reasonably user‐friendly and intuitive model for arriving at a company's optimal, or value‐maximizing, leverage ratio that is based on the estimation of company‐specific cost and benefit functions for debt financing. The benefit functions are downward‐sloping,...