Session 20 (Undergraduate): The Cost of Capital and Financing Mix

In this session, we continued our discussion of the cost of capital approach to deriving an optimal financing mix: the optimal one is the debt ratio that minimizes the cost of capital. To estimate the cost of capital at different debt ratios, we estimated the levered beta/ cost of equity at each debt ratio first and then the interest coverage ratio/synthetic rating/cost of debt at each debt ratio, taking care to ensure that if the interest expenses exceeded the operating income, tax benefits would be lost.