EZ

Eduzan

Learning Hub

Eduzan
Eduzan / 03 Corporate Finance

Corp 3 – Cost of Capital_ Advanced Topics

Worked examples are fully visible. Check-yourself items are study aids you can reveal one at a time.

The weighted average cost of capital is the return an issuer must earn on its assets to satisfy every provider of capital at once. Written across the three capital types a listed company typically uses, it is a weighted blend of the after-tax cost of debt, the cost of preferred equity and the cost of common equity.

The three weights are all non-negative and sum to 1.0.

The formula is trivial. Populating it is not. Three features of the task make a WACC estimate a judgement rather than a measurement.

  • Each component cost can be estimated by several different methods, and no single method is the right one. Two competent analysts applying different methods to the same company will disagree.
  • The weights are supposed to reflect a long-term target capital structure, which may or may not resemble the capital structure the company happens to run today.
  • The marginal tax rate has to be estimated, and it may differ from the company average or effective tax rate reported in the financial statements.

Because every one of those choices feeds through to a discount rate, and every discount rate feeds through to a valuation, the assumptions behind a WACC estimate matter as much as the arithmetic. This reading works through each component in turn and, at every stage, names the choice the analyst is making.

The two component costs, in outline

Debt sits ahead of equity in the capital structure and therefore carries lower risk and a lower cost. Before the tax deductibility of interest is considered, the cost of debt can be decomposed into a benchmark risk-free rate plus a credit spread that pays investors for the risk in that particular security.

The credit spread is where company-specific information enters. It reflects the riskiness of the business model, expected profitability and growth, the applicable tax rates, the protective covenants written into the debt, the leverage policy the company follows and any signalled change to it, the maturity and callability of the issue, and the nature and liquidity of the assets and operations standing behind it.

The cost of equity is harder, because it is not observable. A recent bond issue gives a usable read on the pre-tax cost of debt; nothing equivalent exists for equity, so the required return of equity investors must be modelled. The single-factor capital asset pricing model remains the most common approach in practice. It says that expected return is the risk-free rate plus the equity risk premium scaled by the asset sensitivity to the market factor.

The ERP is the extra return equity investors demand over the risk-free rate; beta scales it to the individual security.

Preferred equity sits between the two. It normally carries a stated dividend rate and a claim on assets ranking ahead of common equity, so the risk premium investors demand on a preferred issue is smaller than the premium on the same company common equity. Preferred equity is therefore cheaper than common equity and dearer than debt. That ordering is a useful sanity check, and Section 10 shows a case where a published model estimate violates it.

Figure 1: Where a cost of capital estimate comes from
Top-down, external risk-free rate, ERP, aggregate spreads, law, tax regime Bottom-up, specific cash flow volatility, assets, leverage, security features Cost of debt risk-free rate plus a credit spread Cost of equity risk-free rate plus beta times the ERP WACC blended at target weights
Every arrow is a main channel, which is why all four are drawn the same way: each driver set feeds both component costs. Top-down conditions set the risk-free benchmark that both estimates start from, the general level of credit spreads and the ERP; bottom-up characteristics set the issuer credit spread on the debt side and the beta on the equity side. The two component costs are then blended at target weights to give the WACC.
End of lesson.