De la solution d'un problème concret (projet d'investissement soumis à une fiscalité spécifique) à une avancée théorique (unicité des méthodes de calcul de Valeurs actuelles)

The starting point of this article deals with an applied problem of capital budgeting that a firm whose projects are subject to various tax rates (as is often the case in the oil industry) may encounter: how to value a project partly financed by borrowing and subject to a different tax rate from the one used to determine the discount rate of the firm? Surprisingly enough, answering this question led us to develop a unique formulation of the different conventional investment decision methods (standard WACC, Arditti-Levy, Equity Residual, Myers? APV). Moreover, we generalize the Modigliani-Miller relationship to the case of a project of any duration. Classification JEL : G30, G31, G32