Financial decision making suggests that we should invest in projects that yield a return greater than the minimum acceptable discount rate (e.g. NPV>0 or IRR>r) also known as the hurdle rate
So, how do we find such a hurdle rate?
Financial resources are limited, and there are always alternative uses for capital. Thus all projects will have to return some minimum hurdle rate before being deemed acceptable.
This hurdle will be higher for riskier projects than for safer projects.
Hurdle rate = Riskless Rate + Risk Premium
The two basic questions that every risk and return model in finance tries to answer are:
Assume I borrow $100 and promise to pay $105 in one year
If the annual (risk-free) opportunity cost of money is 5%, then the value of next year's $105 today is
Now say there is a 87.5% chance that I will give you $120 next year (a 12.5% chance that you get nothing) to borrow $100 today.
Note if we multiply through the probability, we could rewrite this as \((120/1.20) + (0/8.4) = 100\)
Thus, a 87.5% chance of 120 at 5% discount rate is equivalent to a 100% chance of 120 at 20% discount rate. So to adjust for risk, we can just discount at a rate higher than the risk-free rate
Returns generally are uncertain (opportunity and danger).
The greater the chance of a return below the expected return, the greater the risk.
Risk Premium
A return is the change in price of an asset, investment, or project over time
Often represented in terms of price change or percentage change
Thus, for the same future cash flows, a lower price today for an asset leads to a higher return
Expected returns are based on the probabilities of possible outcomes
"Expected" means average if the process is repeated many times
What are the expected returns for & ?
| State | Probability | ||
|---|---|---|---|
| Boom | % | % | |
| Normal | % | % | |
| Recession | % | % |
For : E[R] = () + () + () = %
For : E[R] = () + () + () = %
Both measure the volatility of returns
Variance is the weighted average of squared deviations
Standard deviation is the square root of the variance (\(\sigma\))
| State | Probability | ABC, Inc. (%) |
|---|---|---|
| Boom | ||
| Normal | ||
| Slowdown | ||
| Recession |
What is the expected return, variance, and standard deviation?
E[R] = () + () + () + () = %
Variance = (-)^2 + (-)^2 + (-)^2 + (-)^2 = <\span>
Standard Deviation = sqrt() = %
50/50 investment between Fortune Brands & Homestake Mining
| State | Probability | Fortune | Homestake |
|---|---|---|---|
| Boom | 0.4 | 30% | -5% |
| Bust | 0.6 | -10% | 25% |
Expected return and standard deviation
50/50 investment between Fortune Brands & Homestake Mining
| State | Probability | Fortune | Homestake | 50/50 Portfolio |
|---|---|---|---|---|
| Boom | 0.4 | 30% | -5% | .5(30%)+.5(-5%)=12.5% |
| Bust | 0.6 | -10% | 25% | .5(-10%)+.5(25%)=7.5% |
Expected return
E(R_Fortune)=.4(30%)+.6(-10%)=6%
E(R_Homestake)=.4(-5%)+.6(25%)=13%
E(R_Portfolio)=.4(12.5%)+.6(7.5%)=9.5%
50/50 investment between Fortune Brands & Homestake Mining
| State | Probability | Fortune | Homestake | 50/50 Portfolio |
|---|---|---|---|---|
| Boom | 0.4 | 30% | -5% | .5(30%)+.5(-5%)=12.5% |
| Bust | 0.6 | -10% | 25% | .5(-10%)+.5(25%)=7.5% |
Standard Deviation
Variance(Fortune)=.4(30-6)^2+.6(-10-6)^2
SD(Fortune)=19.6%
Variance(Homestake)=.4(-5-13)^2+.6(25-13)^2
SD(Homestake)=14.7%
SD(Portfolio)= 2.45%
| State | Probability | IBM | HP |
|---|---|---|---|
| Boom | % | % | |
| Normal | % | % | |
| Recession | % | % |
What is the expected return and standard deviation for a portfolio with an investment of in IBM and in HP?
Weight in IBM = / ( + ) =
Weight in HP = / ( + ) =
| State | Prob | IBM | HP | Portfolio Returns |
|---|---|---|---|---|
| Boom | % | % | () + () = % | |
| Normal | % | % | () + () = % | |
| Recession | % | % | () + () = % |
E[R] on Portfolio
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E[R] on Portfolio = %
| State | Prob | Port Ret | Squared Difference |
|---|---|---|---|
| Boom | % | (% - %)\(^2\) = | |
| Normal | % | (% - %)\(^2\) = | |
| Recession | % | (% - %)\(^2\) = |
Standard Deviation of the Portfolio
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Systematic
Unsystematic
Investment in several different asset classes
Can substantially reduce returns variability without reducing expected returns
A minimum level of risk cannot be diversified away
| Security | Weight | Beta |
|---|---|---|
| A | ||
| B | ||
| C | ||
| D |
Portfolio betas are linearly additive since no further diversification is possible
What is the portfolio beta?
\(\beta_P = w_1 \beta_1 + w_2 \beta_2 + w_3 \beta_3 + \dotsb =\)
\(\beta_P\) =
()
+
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+
()
+
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\(\beta_P\) =
Diversifiable or unsystematic risk can be eliminated by combining assets into a portfolio
Total risk = systematic risk + unsystematic risk
| Standard Deviation | Beta | |
|---|---|---|
| Boeing | % | |
| Merck | % |
Which has more total risk?
Which has more systematic risk?
Which should have the higher expected return?
Since has the largest standard deviation, it has the most total risk.
Since has the largest beta, it has the most systematic risk.
There is no reward (in expectation) for bearing unnecessary risk. Therefore the stock with the highest beta, , should also have the higher expected return.
Reward for bearing risk
Beta (\(\beta\)) measures systematic risk
What does beta tell us?
Risk premium = expected return – risk-free rate
Higher beta ~ higher risk premium
Can estimate the expected return when we know this relationship
We know two assets and their returns by definition
Slope of beta & return relationship
What if an asset plots above the line?
What if an asset plots below the line?
SML represents market equilibrium
SML slope is the reward-to-risk ratio:
Securities are in equilibrium: "Fairly priced" and thus pushed towards the Security Market Line
One cannot "beat the market" except through good luck or inside information.
Doesn't mean you can't make money.
Weak Form EMH
Semi-Strong Form EMH
Strong Form EMH
"On the Impossibility of Informationally Efficient Markets" Grossman and Stiglitz (1980)
CAPM — relationship between risk and return for asset X
\(E[R_X] = R_f + \beta_X (E[R_M] - R_f)\)
If we know an asset's systematic risk, we can use the CAPM to determine its expected return
If the risk-free rate is 4% and the market risk premium is 6%, what is the expected return for each?
| Security | Beta | Expected Return |
|---|---|---|
| A | 2.0 | |
| B | 0.8 |
If the risk-free rate is 4% and the market risk premium is 6% (implies expected market return is 4%+6%=10%), what is the expected return for each?
| Security | Beta | Expected Return |
|---|---|---|
| A | 2.0 | 4%+(2.0*6%)=16% |
| B | 0.8 | 4%+(0.8*6%)=8.8% |
The top-down beta for a firm comes from a regression
The bottom-up beta can be estimated by doing the following:
The bottom-up beta will give you a better estimate when:
Product or industry factors
Operating leverage
Financial leverage
Industry Effects: The beta value for a firm depends upon the sensitivity of the demand for its products and services and of its costs to macroeconomic factors that affect the overall market.
Operating leverage refers to the proportion of the total costs of the firm that are fixed.
Other things remaining equal, higher operating leverage results in greater earnings variability which in turn results in higher betas.
As firms borrow, they create fixed costs (interest payments) that make their earnings to equity investors more volatile.
This increased earnings volatility which increases the equity beta
You are advising a very risky software firm on the right cost of equity to use in project analysis. You estimate a beta of 3.0 for the firm and come up with a cost of equity of 18.46%. The CFO of the firm is concerned about the high cost of equity and wants to know whether there is anything he can do to lower his beta.
How do you bring your beta down?
Should you focus your attention on bringing your beta down?
The standard procedure for estimating betas is to regress stock returns (\(R_j\)) against market returns (\(R_M\))
\( R_j = a + b (R_M) \)
The slope of the regression corresponds to the beta of the stock, and measures the riskiness of the stock.
The intercept of the regression provides a simple measure of performance during the period of the regression, relative to CAPM.
$$ \begin{aligned} R_j &= R_f + b (R_M - R_f)\\ &= R_f (1-b) + b (R_M) \qquad \text{Capital Asset Pricing Model} \\ R_j &= a + b (R_M) \qquad \qquad \qquad \text{Regression Equation} \end{aligned} $$If \( a > R_f (1 - b) \): Stock did better than expected during regression period
If \( a < R_f (1 - b) \): Stock did worse than expected during regression period
Recall, we divided risk into diversifiable and non-diversifiable risk.
The R squared (\(R^2\)) of the regression provides an estimate of the proportion of the risk (variance) of a firm that can be attributed to market risk (also called systematic risk).
The balance (1 - \(R^2\)) can be attributed to firm specific risk.
Period used: 5 years (2010-2014)
Return Interval = Daily
Market Index: S&P 500 Index
Using daily returns from 2010 to 2014, we ran a regression of returns on Churchill stock against the S&P 500. The output is below:
Slope of the Regression of 1.048 is the beta
Regression parameters are always estimated with error. The error is captured in the standard error of the beta estimate, which in this case is 0.035.
Assume that I asked you what Churchill's true beta is, after this regression.
R Squared = 42%
This implies that
The firm-specific risk is diversifiable and will not be rewarded
You are a diversified investor trying to decide whether you should invest in Churchill or Amgen. They both have betas of 1.048, but Churchill has an R Squared of 42% while Amgen's R squared of only 14.5%. Which one would you invest in?
Would your answer be different if you were an undiversified investor?
Inputs to the expected return calculation
$$ \begin{aligned} \text{Churchill's Beta} = 1.048& \\ \text{Risk-free Rate} = 4.00\%& \text{ (U.S. ten-year T.Bond rate)} \\ \text{Risk Premium} = 4.82\%& \text{(Approximate historical} \\ & \text{ premium: 1928-2003)} \end{aligned} $$As a potential investor in Churchill, what does this expected return of 9.05% tell you?
Assume now that you are an active investor and that your research suggests that an investment in Churchill will yield 12.5% a year for the next 5 years.
Management at Churchill
In other words, Churchill's cost of equity is 9.05%.