Cost of Capital: Meaning, Sources & WACC Calculation

No investor gives money for free. Lenders expect interest, and shareholders expect dividends and capital appreciation. The Cost of Capital is the minimum rate of return that a business must earn on its investments so that the market value of its equity shares remains unchanged.

1. Significance of Cost of Capital

In corporate finance, Cost of Capital serves as:

1. The Cut-off / Hurdle Rate: Used in Capital Budgeting decisions. If a project’s expected return is 14% and the Cost of Capital is 11%, the project is profitable and accepted.
2. The Discount Rate: Used to discount future cash flows to compute Net Present Value (NPV).
3. Designing Capital Structure: Helps the CFO design an optimal mix of debt and equity that minimizes the overall Weighted Average Cost of Capital (WACC).

2. Specific Costs of Different Sources of Capital

A firm raises long-term funds from four primary sources:

1. Debt Capital (Kd)
2. Preference Share Capital (Kp)
3. Equity Share Capital (Ke)
4. Retained Earnings (Kr)

Let us examine the formulas and logic for each:

3. Cost of Debt (Kd)

Debt is generally the cheapest source of capital because:

• Lenders face the lowest risk (first claim on assets).
• Interest paid on debt is a tax-deductible expense, which creates an Interest Tax Shield.

Formulas for Cost of Debt:

A. Irredeemable (Perpetual) Debt:

• Pre-Tax Cost:

  Kd (Pre-Tax) = Interest (I) / Net Proceeds (NP)

• Post-Tax Cost (Actual Cost to the Company):

  Kd (Post-Tax) = [Interest (I) × (1 - Tax Rate)] / Net Proceeds (NP)

B. Redeemable Debt (Repaid after n years):

Kd (Post-Tax) = [I × (1 - t) + (RV - NP) / n] / [(RV + NP) / 2]

Where:

• I: Annual interest payable
• t: Corporate tax rate (e.g., 0.30 for 30%)
• NP: Net proceeds realized after discount or flotation costs
• RV: Redeemable value at maturity
• n: Number of years to maturity

4. Cost of Preference Share Capital (Kp)

Preference shares carry a fixed dividend rate, but dividends are paid after corporate income tax (hence, preference dividends receive no tax shield).

Formulas:

A. Irredeemable Preference Shares:

Kp = Annual Preference Dividend (PD) / Net Proceeds (NP)

B. Redeemable Preference Shares:

Kp = [PD + (RV - NP) / n] / [(RV + NP) / 2]

5. Cost of Equity Capital (Ke)

Equity shareholders bear the highest risk and demand the highest return. Management can estimate Ke using three established approaches:

A. Dividend Yield Method

Assumes dividends remain constant indefinitely:

Ke = Dividend per Share (D) / Current Market Price (P0)

B. Dividend Growth Model (Gordon’s Model)

When dividends are expected to grow at a constant annual percentage rate (g):

Ke = [D1 / P0] + g

Where:

• D1: Expected dividend at the end of Year 1 = D0 × (1 + g)
• P0: Current market price per share
• g: Constant annual dividend growth rate

C. Capital Asset Pricing Model (CAPM) Approach

Ke = Rf + β × (Rm - Rf)

Where:

• Rf: Risk-free rate of return (e.g., Govt Bond yield)
• β (Beta): Systematic risk coefficient of the company’s stock
• Rm: Expected return on the overall stock market portfolio
• (Rm - Rf): Market Risk Premium

6. Cost of Retained Earnings (Kr)

Retained earnings are profits ploughed back into the firm rather than distributed as dividends.

• Retained earnings are NOT free of cost! They involve an Opportunity Cost (the return shareholders could have earned if the money had been paid out as dividends and reinvested elsewhere).
• Generally:

  Kr = Ke × (1 - Personal Tax Rate) × (1 - Brokerage Cost)

• In basic college problems without personal taxes, Kr is assumed equal to Ke.

7. Weighted Average Cost of Capital (WACC / Ko)

WACC is the overall cost of capital of the firm, calculated as the weighted average of the specific costs of each individual component of capital, where weights reflect the proportion of each source in the total capital structure.

Computation Steps:

1. Calculate the specific cost of each source (Kd, Kp, Ke, Kr).
2. Determine the weight (proportion) of each source using either Book Value Weights or Market Value Weights.
3. Multiply each specific cost by its respective weight.
4. Sum up the weighted costs to get WACC (Ko).

Solved Practical Numerical Problem:

A company has the following capital structure:

Step-by-Step WACC Calculation:

Overall WACC (Ko) = 12.32%

Decision Rule: The company must not accept any new investment project that generates an internal return less than 12.32%!

8. Summary & Quick Revision Checklist

• Cost of Capital: Minimum hurdle rate required to maintain the market value of the company’s shares.
• Cost of Debt (Kd): Lowest cost source due to senior claim and tax deductibility of interest [I × (1 - t)].
• Cost of Preference Shares (Kp): Fixed dividend rate without corporate tax benefit.
• Cost of Equity (Ke): Highest cost source; estimated via Gordon’s Growth Model (D1/P0 + g) or CAPM.
• WACC (Ko): The composite hurdle rate computed by multiplying specific costs with their proportionate weights.