Weighted Average Cost of Capital – Chapter 13
Objectives and Big-Picture Purpose
- Understand what drives a firm’s overall cost of money, i.e., its Weighted Average Cost of Capital (WACC).
- Measure/estimate the annual cost of each financing source (debt, preferred stock, common equity).
- Combine those costs using market-value weights to get one blended rate.
- Primary uses:
- Discount rate for Net Present Value (NPV) analysis.
- Hurdle rate to compare against Internal Rate of Return (IRR).
- Overall valuation of a firm or of individual projects.
- Value-creation rule:
- If project IRR > WACC ⇒ expected to create shareholder value (e.g., IRR vs. WACC ).
Financing Sources & Terminology
- Debt (bonds, notes) → interest is tax-deductible.
- Preferred stock → fixed dividend, no maturity, ranks above common but below debt.
- Common equity → residual ownership; highest risk, highest required return.
- Key distinction: Market value (current economic worth) vs. Book value (historical accounting amounts).
Step 1 – Determine Market-Value Weights
- Collect market value for EACH capital component.
- Debt market value = Book/face value × current bond price (% of par).
- Preferred & common equity market value = Shares outstanding × market price per share.
- Total capital .
- Compute weights:
Example (Cannae):
- Book debt , trades at of face ⇒ .
- Book equity , but 1 000 000 shares × ⇒ .
- .
- (book-value split would have been 50/50 ‑- illustrates why market values matter).
Real-firm capital structures (market values):
- Southern Co: , (mainly equity but sizable debt).
- Amazon: , (≈ debt, equity).
Step 2 – Estimate Component (Marginal) Costs
2A – Cost of Debt
- Use yield to maturity (YTM) on outstanding bonds (solve for on calculator).
- Example (AT&T):
- Pretax YTM
- After-tax cost
- Reason: Interest expense shelters taxes; multiply by .
2B – Cost of Preferred Stock
- Constant-dividend security (no growth).
- Rearranged Gordon formula (zero-growth):
- Example (AT&T preferred):
- Price , dividend ⇒
- Example (Arlington 7% Series B cum.):
- Face , coupon rate ⇒ dividend .
- Market price ⇒
2C – Cost of Common Equity
Two mainstream methods:
- CAPM / Security Market Line
- Example (AT&T): market risk premium
- Dividend Growth (Gordon) Model (constant-growth firms only)
- Gives an alternative figure; analysts may average the two if both are credible.
Hierarchy of risk & cost: rD(1-T) < r{PS} < r_{CE}.
Step 3 – Compute WACC
General formula (after-tax for debt only):
AT&T Illustration:
- Market values:
- Weights:
- Component costs:
- WACC:
Target Drill Practice (data provided):
- Pretax tax rate weights
- Compute: (implied given solution).
Applications & Managerial Interpretation
- Use WACC as discount rate in capital budgeting:
- NPV: discount project cash flows at WACC.
- IRR rule: accept if \text{IRR} > \text{WACC}.
- Higher risk (β, leverage, sector) ⇒ higher WACC ⇒ tougher hurdle.
- Firm-wide vs. Project-specific: Ideally match project risk; otherwise WACC is default.
Snapshot of Actual Firms (illustrative table in lecture)
- Low-risk example: Hershey
- WACC .
- High-risk example: AMD
- much larger equity cost.
- WACC
- Pattern: Tech/manufacturing & highly levered firms sit at lower list positions (high WACC); stable consumer staples/utilities at upper positions (low WACC).
- Always verify: because equity holders are residual claimants.
Ethical, Philosophical & Practical Notes
- Choosing book values understates (or misstates) current economics; ethical duty to use market data to inform shareholders accurately.
- Under-estimating WACC may lead to over-investment; over-estimating may cause firms to reject value-adding projects.
- Tax deductibility of interest creates incentives for leverage; however, excessive debt raises bankruptcy risk – a trade-off tied back to WACC.
Comprehensive Procedure Checklist
- Gather current market values for debt, preferred, and equity.
- Compute weights by dividing each component by total .
- Estimate costs:
- Debt: solve for YTM, then apply
- Preferred:
- Equity: use CAPM, and/or
- Plug into WACC formula; present percentage to at least one decimal place.
- Apply WACC as discount/hurdle in all valuation exercises.
Connections to Earlier Material
- Bond valuation chapter taught solving for YTM (link to Step 2A).
- Dividend Discount Model covered formula (link to 2B & 2C).
- CAPM & β estimation came from risk-return lectures (foundation for equity cost).
End-of-Chapter Summary Bullets
- WACC captures blended, opportunity cost of capital using market values.
- Only debt enjoys a tax shield ⇒ adjust it after tax.
- Equity is always costlier than debt; firm risk profile drives both.
- Correct WACC is central to sound capital budgeting and firm valuation.
- Methodological discipline: use up-to-date market inputs, verify assumptions (constant growth, β stability, tax rate).