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Module 5 · Risk, return and the cost of equity Core

Investors demand a higher expected return for bearing more risk. The question is which risk counts.

RS 202 Corporate Finance · By · ~6 min read, ~2 hr with practice · Not started

By the end of this module you'll be able to

  • Separate diversifiable from market risk, apply the CAPM, and adjust beta for leverage.

Two kinds of risk

Company-specific (unsystematic) risk comes from events affecting one firm: a product recall, a lawsuit, a strike. It can be diversified away by holding many stocks. Market (systematic) risk comes from economy-wide events: recessions, interest rates, inflation. It cannot be diversified away. Because diversification is nearly free, the market pays a premium only for systematic risk.

Beta

Beta measures how much a stock moves with the market. A beta of 1.0 moves with the market; 1.5 moves 50% more; 0.5 moves half as much. Beta is estimated by regressing the stock's returns on the market's returns, typically over two to five years.

The capital asset pricing model

Cost of equity = risk-free rate + beta x equity risk premium

Leverage and beta

Debt makes equity riskier, so observed (levered) betas reflect each company's capital structure. To compare companies or to value a private firm, remove the effect of debt, then add back the target's own leverage.

Example: a peer has a levered beta of 1.2, debt/equity of 0.5 and a 25% tax rate. Unlevered beta = 1.2 / 1.375 = 0.873. For a target with debt/equity of 1.0, relevered beta = 0.873 x 1.75 = 1.53.

Alternative: the dividend growth model

Cost of equity = next year's dividend / price + growth rate. A stock at $40 paying $2 next year and growing 4% implies 5% + 4% = 9%.

Adjustments used in practice

Some analysts add a size premium for small companies, a country risk premium for emerging markets, or a company-specific premium for private firms. Each is a judgment; state it and keep it modest.

Limits of the CAPM

Beta is unstable over time, the ERP cannot be observed directly, and research shows other factors (size, value, profitability, momentum) also explain returns. RS 302 covers this. The CAPM remains the standard starting point because it is simple and its inputs are available.

The equity risk premium in practice

There are three ways to estimate it. Historical: the average excess return of stocks over government bonds, which depends heavily on the period and on whether arithmetic or geometric averages are used. Surveys: what CFOs and analysts say they expect. Implied: the rate that equates today's index level with forecast dividends, buybacks and growth. Implied estimates for the US have mostly ranged between about 4% and 6% over recent decades. Most practitioners use a figure in that range and state it.

Worked example 2: a build-up for a private company

A private firm has no traded shares, so its beta comes from listed peers (relevered to 1.3). Risk-free rate 4%, ERP 5%, plus a size premium of 2% and a company-specific premium of 1% for customer concentration.

Cost of equity = 4% + 1.3 x 5% + 2% + 1% = 13.5%

Every premium added is a judgment. Adding 3% for 'risk' to a forecast that already assumes things go wrong double-counts the risk.

Estimating beta well

Choices change the answer: the index (S&P/TSX Composite or a world index), the frequency (weekly or monthly), the period (two or five years) and whether the company's business has changed. Raw betas are noisy and drift toward 1, so services publish adjusted betas, commonly 2/3 x raw beta + 1/3. A raw beta of 1.6 becomes 1.40. An industry average of unlevered betas, relevered to the target's debt, is usually more reliable than one company's own regression.

Worked example 3: a project outside the core business

A retailer with a debt/equity ratio of 0.25 and a 25% tax rate considers a logistics venture. Listed logistics companies have an average unlevered beta of 0.9.

  • Relevered beta = 0.9 x [1 + 0.75 x 0.25] = 0.9 x 1.1875 = 1.07.
  • With a 3.5% risk-free rate and a 5% ERP: cost of equity = 3.5% + 1.07 x 5% = 8.84%.

Using the retailer's own beta would give the wrong rate for this project, higher or lower, depending on how its risk differs.

Country risk

A company with operations in a riskier country may add a country risk premium, often estimated from the spread of that country's US-dollar government bonds over US Treasuries, scaled up for the higher volatility of equities. Apply it in proportion to the company's exposure, not to every company headquartered there.

What the cost of equity is not

It is not the dividend yield, and it is not the return the company 'pays' its shareholders. It is the return investors expect for bearing the risk, and the company must beat it to create value.

Put it into practice

Your mission

Pick one company. Look up its beta from two sources and note the difference. Using the current 10-year government bond yield and a 5% ERP, compute its cost of equity with each beta. Then unlever the beta using its debt/equity ratio.

Look up a company’s numbers →

Educational content only; not investment, tax or legal advice. Companies, tickers and figures are illustrative examples, not recommendations. Rules, rates and limits change, so check current details with the regulator, exchange or tax authority before relying on them. Worked examples are not forecasts. Written by Elizabeta Dimoska. RiskStock is not a registered dealer or adviser.