Title: CHAPTER 5 Risk and Rates of Return
1Principles of Business FinanceFin 510
Dr. Lawrence P. Shao Marshall University Spring
2002
2CHAPTER 5 Risk and Rates of Return
- Stand-alone risk
- Portfolio risk
- Risk return CAPM/SML
3What is investment risk?
Investment risk pertains to the probability of
earning less than the expected return. The
greater the chance of low or negative returns,
the riskier the investment.
4Annual Total Returns,1926-1996
Average Standard Return Deviation Distribution
Large-companystocks 12.7
20.3 Small-companystocks
17.7 34.1 Long-termcorporate bonds
6.0 8.7 Long-termgovernment
5.4 9.2 Intermediate-termgovernme
nt 5.4 5.8 U.S.
Treasurybills 3.8
3.3 Inflation 3.2
4.5
-90 0 90
5Investment Alternatives(Given in the problem)
Economy
Prob.
T-Bill
HT
Coll
USR
MP
Recession 0.1 8.0 -22.0 28.0
10.0 -13.0 Below avg. 0.2 8.0 -2.0 14.7
-10.0 1.0 Average 0.4 8.0 20.0 0.0 7.0
15.0 Above avg. 0.2 8.0 35.0 -10.0 45.0
29.0 Boom 0.1 8.0 50.0 -20.0 30.0 43.0 1.0
6Do T-bills promise a completelyrisk-free return?
No, T-bills are still exposed to the risk of
inflation. However, not much unexpected inflation
is likely to occur over a relatively short period.
7Do the returns of HT and Coll. move with or
counter to the economy?
- HT With. Positive correlation. Typical.
- Coll Countercyclical. Negative correlation.
Unusual.
8Calculate the expected rate of return on each
alternative
k expected rate of return.
kHT (-22)0.1 (-2)0.20 (20)0.40
(35)0.20 (50)0.1 17.4.
9k
HT
17.4
Market
15.0
USR
13.8
T-bill
8.0
Coll.
1.7
HT appears to be the best, but is it really?
10Whats the standard deviationof returns for each
alternative?
11sT-bills 0.0.
sColl 13.4. sUSR 18.8. sM 15.3.
sHT 20.0.
12- Standard deviation (si) measures total, or
stand-alone, risk. - The larger the si , the lower the probability
that actual returns will be close to the expected
return.
13Expected Returns vs. Risk
Expected
Risk, s
Security
return
HT 17.4 20.0 Market 15.0 15.3 USR 13.8
18.8 T-bills 8.0 0.0 Coll. 1.7 13.4
Seems misplaced.
14Coefficient of Variation (CV)
Standardized measure of dispersion about the
expected value
Std dev s
CV .
Mean
k
Shows risk per unit of return.
15Portfolio Risk and Return
Assume a two-stock portfolio with 50,000 in HT
and 50,000 in Collections.
Calculate kp and sp.
16Portfolio Return, kp
kp is a weighted average
n
kp S wiki.
i 1
kp 0.5(17.4) 0.5(1.7) 9.6.
kp is between kHT and kCOLL.
17Alternative Method
Estimated Return
Economy
Prob.
HT
Coll.
Port.
Recession 0.10 -22.0 28.0 3.0 Below avg.
0.20 -2.0 14.7 6.4 Average 0.40 20.0 0.0
10.0 Above avg. 0.20 35.0 -10.0 12.5 Boom
0.10 50.0 -20.0 15.0
kp (3.0)0.10 (6.4)0.20 (10.0)0.40
(12.5)0.20 (15.0)0.10 9.6.
18 3.3
CVp 0.34.
9.6
19- sp 3.3 is much lower than that of either stock
(20 and 13.4). - sp 3.3 is lower than average of HT and Coll
16.7. - \ Portfolio provides average k but lower risk.
- Reason negative correlation.
20General statements about risk
- Most stocks are positively correlated. rk,m
0.65. - s 35 for an average stock.
- Combining stocks generally lowers risk.
21Returns Distribution for Two Perfectly Negatively
Correlated Stocks (r -1.0) and for Portfolio WM
Stock W
Stock M
Portfolio WM
.
.
.
.
25
25
25
.
.
.
.
.
.
.
15
15
15
0
0
0
.
.
.
.
-10
-10
-10
22sp ()
Company Specific Risk
35
Stand-Alone Risk, sp
20 0
Market Risk
10 20 30 40 2,000
Stocks in Portfolio
23- As more stocks are added, each new stock has a
smaller risk-reducing impact. - sp falls very slowly after about 40 stocks are
included. The lower limit for sp is about 20
sM .
24Stand-alone Market Firm-specific
risk risk risk
Market risk is that part of a securitys
stand-alone risk that cannot be eliminated by
diversification. Firm-specific risk is that part
of a securitys stand-alone risk which can be
eliminated by proper diversification.
25Beta measures a stocks market risk. It shows a
stocks volatility relative to the market.
- Beta shows how risky a stock is if the stock is
held in a well-diversified portfolio.
26How are betas calculated?
- Run a regression of past returns on Stock i
versus returns on the market. Returns D/P g. - The slope of the regression line is defined as
the beta coefficient.
27Illustration of beta calculation
Regression line ki -2.59 1.44 kM
.
20 15 10 5
.
Year kM ki 1 15 18 2 -5 -10 3 12 16
_
-5 0 5 10 15 20
kM
-5 -10
.
28- If beta 1.0, average stock.
- If beta gt 1.0, stock riskier than average.
- If beta lt 1.0, stock less risky than average.
- Most stocks have betas in the range of 0.5 to 1.5.
29 Expected Risk Security Return (Beta)
HT 17.4 1.29 Market 15.0 1.00 USR 13.8
0.68 T-bills 8.0 0.00 Coll. 1.7 -0.86
Riskier securities have higher returns, so the
rank order is OK.
30Use the SML to calculate therequired returns.
SML ki kRF (kM - kRF)bi .
- Assume kRF 8.
- Note that kM kM is 15. (Equil.)
- RPM kM - kRF 15 - 8 7.
31Required Rates of Return
kHT 8.0 (15.0 - 8.0)(1.29) 8.0
(7)(1.29) 8.0 9.0 17.0.
kM 8.0 (7)(1.00) 15.0. kUSR 8.0
(7)(0.68) 12.8. kT-bill 8.0
(7)(0.00) 8.0. kColl 8.0
(7)(-0.86) 2.0.
32Expected vs. Required Returns
k
k
HT 17.4 17.0 Undervalued k gt k Market
15.0 15.0 Fairly valued USR 13.8 12.8
Undervalued k gt k T-bills 8.0 8.0 Fairly
valued Coll. 1.7 2.0 Overvalued k lt k
33Calculate beta for a portfolio with 50 HT and
50 Collections
bp Weighted average 0.5(bHT) 0.5(bColl)
0.5(1.29) 0.5(-0.86) 0.22.
34The required return on the HT/Coll. portfolio is
kp Weighted average k 0.5(17)
0.5(2) 9.5. Or use SML kp kRF (kM -
kRF) bp 8.0 (15.0 - 8.0)(0.22)
8.0 7(0.22) 9.5.
35If investors raise inflation expectations by 3,
what would happen to the SML?
36Required Rate of Return k ()
D I 3
New SML
SML2
SML1
18 15 11 8
Original situation
0 0.5 1.0 1.5 Risk, bi
37If inflation did not changebut risk aversion
increasedenough to cause the marketrisk premium
to increase by3 percentage points, whatwould
happen to the SML?
38After increase in risk aversion
Required Rate of Return ()
SML2
kM 18 kM 15
SML1
18 15
D RPM 3
8
Original situation
Risk, bi
1.0
39- Investors seem to be concerned with both market
risk and total risk. Therefore, the SML may not
produce a correct estimate of ki - ki kRF (kM - kRF)b ?