Finance & Accounting
Weighted Average Cost of Capital (WACC)이란 무엇인가요?
정의
WACC is the average rate a company must earn on its investments to satisfy all its capital providers — debt holders and equity holders — weighted by their proportion in the capital structure. It is the discount rate used in DCF (discounted cash flow) valuations and represents the minimum return a company must generate to create value.
WACC = (E/V × Re) + (D/V × Rd × (1 − Tax Rate)), where E = market value of equity, D = market value of debt, V = E + D, Re = cost of equity, Rd = cost of debt. Cost of equity is typically estimated using the Capital Asset Pricing Model (CAPM): Re = Risk-Free Rate + Beta × Market Risk Premium. Debt is cheaper than equity (and tax-deductible), so companies with more debt tend to have lower WACCs — up to a point where financial distress risk increases the cost of both. WACC is the hurdle rate in project evaluation: projects returning more than WACC create value; projects returning less destroy it. In DCF analysis, a 1% change in WACC can change enterprise value by 10–20% — making WACC estimation one of the most consequential and debated inputs in financial modeling.
왜 중요한가
WACC is the foundation of business valuation and capital allocation. If you are raising capital, evaluating acquisitions, or building a financial model for investors, understanding your cost of capital is essential. A financial advisor or fractional CFO can build a defensible WACC calculation, model capital structure scenarios, and help you understand how financing decisions affect your cost of capital.