Thus, the equity beta of a company is determined both by the riskiness of the business it
operates in, as well as the amount of financial leverage risk it has taken on. Since
financial leverage multiplies the underlying business risk, it stands to reason that firms
that have high business risk should be reluctant to take on financial leverage. It also
stands to reason that firms which operate in relatively stable businesses should be much
more willing to take on financial leverage. Utilities, for instance, have historically had
high debt ratios, but have not had high betas, mostly because their underlying businesses
have been stable and fairly predictable.
Breaking risk down into business and financial leverage components also
provides some insight into why companies have high betas, since they can end up with
high betas in one of two ways - they can operate in a risky business, or they can use very
high financial leverage in a relatively stable business.
Illustration 4.4: Effects of Financial Leverage on betas: Disney
From the regression for the period from 1999 to 2003, Disney had a beta of 1.01.
To estimate the effects of leverage on Disney, we began by estimating the average
debt/equity ratio between 1999 and 2003, using market values for debt and equity.
Average Market Debt/Equity Ratio between 1999 and 2003 = 27.5%
The unlevered beta is estimated using a marginal corporate tax rate of 37.3%:
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Unlevered Beta = Current Beta / (1 + (1 - tax rate) (Average Debt/Equity))
= 1.01 / (1 + (1 - 0.373)) (0.275) = 0.8615
The levered beta at different levels of debt can then be estimated:
Levered Beta = Unlevered Beta * [1 + (1 - tax rate) (Debt/ Equity)]
For instance, if Disney were to increase its debt equity ratio to 10%, its equity beta will
be
Levered Beta (@10% D/E) = 0.8615*(1+ (1 - 0.373) (0.10)) = 0.9155
If the debt equity ratio were raised to 25%, the equity beta would be
Levered Beta (@25% D/E) = 0.8615 *(1+ (1 - 0.373) (0.25)) = 1.00
36
The marginal corporate tax rate in the United States in 2003 was 35%. The marginal state and local tax
rates, corrected for federal tax savings, is estimated by Disney in its annual report to be 2.3%. Disney did
report some offsetting tax benefits that reduced their effective tax rate to 35%. We assumed that these
offsetting tax benefits were temporary.