Title: Principles of Managerial Finance Brief Edition
1Principles of Managerial FinanceBrief Edition
Risk and Return
2Learning Objectives
- Understand the meaning and fundamentals of risk,
return, and risk aversion. - Describe the procedures for assessing the risk of
a single asset. - Discuss the risk measurement for a single asset
using the standard deviation and coefficient of
variation. - Understand the risk and return characteristics of
a portfolio in terms of correlation and
diversification and the impact of international
assets on a portfolio.
3Learning Objectives
- Review the two types of risk and the derivation
and role of beta in measuring the relevant risk
of both an individual security and a portfolio. - Explain the capital asset pricing model (CAPM)
and its relationship to the security market line
(SML).
4Introduction
- If everyone knew ahead of time how much a stock
would sell for some time in the future, investing
would be simple endeavor. - Unfortunately, it is difficult -- if not
impossible -- to make such predictions with any
degree of certainty. - As a result, investors often use history as a
basis for predicting the future. - We will begin this chapter by evaluating the risk
and return characteristics of individual assets,
and end by looking at portfolios of assets.
5Risk Defined
- In the contest of business and finance, risk is
defined as the chance of suffering a financial
loss. - Assets (real or financial) which have a greater
chance of loss are considered more risky than
those with a lower chance of loss. - Risk may be used interchangeably with the term
uncertainty to refer to the variability of
returns associated with a given asset.
6Return Defined
- Return represents the total gain or loss on an
investment. - The most basic way to calculate return is as
follows
kt Pt - Pt-1 Ct Pt-1
- Where kt is the actual, required or expected
return during period t, Pt is the current price,
Pt-1 is the price during the previous time
period, and Ct is any cash flow accruing from the
investment
7Chapter Example
8Single Financial Assets
Historical Return
- Arithmetic Average
- The historical average (also called arithmetic
average or mean) return is simple to calculate. - The text outlines how to calculate this and
other measures of risk and return. - All of these calculations were discussed and
taught in your introductory statistics course. - This slideshow will demonstrate the calculation
of these statistics using EXCEL.
9Single Financial Assets
Historical Return
Arithmetic Average
What you type
What you see
10Single Financial Assets
Historical Risk
- Variance
- Historical risk can be measured by the
variability of its returns in relation to its
average. - Variance is computed by summing squared
deviations and dividing by n-1. - Squaring the differences ensures that both
positive and negative deviations are given equal
consideration. - The sum of the squared differences is then
divided by the number of observations minus one.
11Single Financial Assets
Historical Risk
Variance
12Single Financial Assets
Historical Risk
Variance
13Single Financial Assets
Historical Risk
Variance
What you type
What you see
14Single Financial Assets
Historical Risk
- Standard Deviation
- Squaring the deviations makes the variance
difficult to interpret. - In other words, by squaring percentages, the
resulting deviations are in percent squared
terms. - The standard deviation simplifies interpretation
by taking the square root of the squared
percentages. - In other words, standard deviation is in the
same units as the computed average. - If the average is 10, the standard deviation
might be 20, whereas the variance would be 20
squared.
15Single Financial Assets
Historical Risk
Standard Deviation
What you type
What you see
16Single Financial Assets
Historical Risk
Normal Distribution
R-2?
R-1?
R2?
R1?
R
68
95
17Single Financial Assets
Expected Return Risk
- Investors and analysts often look at historical
returns as a starting point for predicting the
future. - However, they are much more interested in what
the returns on their investments will be in the
future. - For this reason, we need a method for estimating
future or ex-ante returns. - One way of doing this is to assign probabilities
for future states of nature and the returns
that would be realized if a particular state of
nature would occur.
18Single Financial Assets
Expected Return Risk
Expected Return E(R) ? piRi, where pi
probability of the ith scenario, and Ri the
forecasted return in the ith scenario.
19Single Financial Assets
Expected Return Risk
20Single Financial Assets
Expected Return Risk
21Single Financial Assets
Expected Return Risk
22Single Financial Assets
Expected Return Risk
23Single Financial Assets
Coefficient of Variation
- One problem with using standard deviation as a
measure of risk is that we cannot easily make
risk comparisons between two assets. - The coefficient of variation overcomes this
problem by measuring the amount of risk per unit
of return. - The higher the coefficient of variation, the
more risk per return. - Therefore, if given a choice, an investor would
select the asset with the lower coefficient of
variation.
24Single Financial Assets
Coefficient of Variation
25Portfolios of Assets
- An investment portfolio is any collection or
combination of financial assets. - If we assume all investors are rational and
therefore risk averse, that investor will ALWAYS
choose to hold a portfolio rather than a single
asset. - Investors will hold portfolios because he or she
will diversify away a portion of the risk that
is inherent in putting all your eggs in one
basket. - If an investor holds a single asset, he or she
will fully suffer the consequences of poor
performance. - This is not the case for an investor who owns a
portfolio.
26Portfolios of Assets
- Diversification is enhanced depending upon the
extent to which the returns on assets move
together. - This movement is typically measured by a
statistic known as correlation as shown in
Figure 7.3 and 7.4.
27Portfolios of Assets
28Portfolios of Assets
Recall Stocks A and B
29Portfolios of Assets
Portfolio AB (50 in A, 50 in B)
30Portfolios of Assets
Portfolio AB (50 in A, 50 in B)
Where the contents of cell B12 and B13 50 in
this case.
Here are cells B12 and B13
31Portfolios of Assets
Portfolio AB (50 in A, 50 in B)
32Portfolios of Assets
Portfolio AB (40 in A, 60 in B)
Changing the weights
33Portfolios of Assets
Portfolio AB (20 in A, 80 in B)
And Again
34Portfolios of Assets
Portfolio Risk Return
Summarizing changes in risk and return as the
composition of the portfolio changes.
35Portfolios of Assets
Portfolio Risk Return (Perfect Negative
Correlation)
36Portfolios of Assets
Portfolio Risk Return (Perfect Negative
Correlation)
Notice that if we weight the portfolio just right
(50/50 in this case), we can completely eliminate
risk.
37Portfolios of Assets
Portfolio Risk (Adding Assets to a Portfolio)
Portfolio Risk (SD)
Unsystematic (diversifiable) Risk
SDM
Systematic (non-diversifiable) Risk
of Stocks
0
38Portfolios of Assets
Portfolio Risk (Adding Assets to a Portfolio)
Portfolio Risk (SD)
Portfolio of Domestic Assets Only
Portfolio of both Domestic and International
Assets
SDM
of Stocks
0
39Portfolios of Assets
Capital Asset Pricing Model (CAPM)
- If you notice in the last slide, a good part of
a portfolios risk (the standard deviation of
returns) can be eliminated simply by holding a
bunch of stocks. - The risk you cant get rid of by adding stocks
(systematic) cannot be eliminated through
diversification because that variability is
caused by events that affect most stocks
similarly. - Examples would include changes in macroeconomic
factors such interest rates, inflation, and the
business cycle.
40Portfolios of Assets
Capital Asset Pricing Model (CAPM)
- Then in the early 1960s, researchers (Sharpe,
Treynor, and Lintner) developed an asset pricing
model that measures only the amount of
systematic risk a particular asset has. - In other words, they noticed that most stocks go
down when interest rates go up, but some go down
a whole lot more. - They figured that if they could measure this
variability -- the systematic risk -- then they
could develop a model to price assets using only
this risk. - The unsystematic (company-related) risk is
irrelevant because it could easily be eliminated
simply by diversifying.
41Portfolios of Assets
Capital Asset Pricing Model (CAPM)
- To measure the amount of systematic risk an
asset has, they simply regressed the returns for
the market portfolio -- the portfolio of ALL
assets -- against the returns for an individual
asset. - The slope of the regression line -- beta --
measures an assets systematic (non-diversifiable)
risk. - In general, cyclical companies like auto
companies have high betas while relatively
stable companies, like public utilities,have
low betas. - Lets look at an example to see how this works.
42Portfolios of Assets
Capital Asset Pricing Model (CAPM)
- The text goes through a fairly long calculation
to arrive at beta. - We will demonstrate the calculation using the
regression analysis feature in EXCEL. - By the way, its a whole lot faster.
43Portfolios of Assets
Capital Asset Pricing Model (CAPM)
This slide is the result of a regression using
the Excel. The slope of the regression (beta) in
this case is 1.92. Apparently, this stock has a
considerable amount of systematic risk.
44Portfolios of Assets
Capital Asset Pricing Model (CAPM)
45Portfolios of Assets
Capital Asset Pricing Model (CAPM)
46Portfolios of Assets
Capital Asset Pricing Model (CAPM)
47Portfolios of Assets
Capital Asset Pricing Model (CAPM)
- The required return for all assets is composed of
two parts the risk-free rate and a risk premium.
The risk premium is a function of both market
conditions and the asset itself.
The risk-free rate (rf) is usually estimated from
the return on US T-bills
48Portfolios of Assets
Capital Asset Pricing Model (CAPM)
- The risk premium for a stock is composed of two
parts - The Market Risk Premium which is the return
required for investing in any risky asset rather
than the risk-free rate - Beta, a risk coefficient which measures the
sensitivity of the particular stocks return to
changes in market conditions.
49Portfolios of Assets
Capital Asset Pricing Model (CAPM)
- After estimating beta, which measures a specific
assets systematic risk, relatively easy to
estimate variables may be obtained to calculate
an assets required return..
E(Ri) RFR b E(Rm) - RFR, where E(Ri) an
assets expected or required return, RFR the
risk free rate of return, b an asset or
portfolios beta E(Rm) the expected return on
the market portfolio.
50Portfolios of Assets
Capital Asset Pricing Model (CAPM)
Example Calculate the required return for Federal
Express assuming it has a beta of 1.25, the rate
on US T-bills is 5.07, and the expected return
for the SP 500 is 15.
E(Ri) 5.07 1.25 15 - 5.07 E(Ri) 17.48
51Portfolios of Assets
Capital Asset Pricing Model (CAPM)
Graphically
E(Ri)
17.48
15.0
RFR 5.07
beta
1.25
1.0
52Portfolios of Assets
Capital Asset Pricing Model (CAPM)
53Portfolios of Assets
Capital Asset Pricing Model (CAPM)
SML
k
20
15
10
5
B
1
2
MSFT
FPL
54Portfolios of Assets
Capital Asset Pricing Model (CAPM)
SML1
k
20
SML2
15
Shift due to change in market return from 15 to
12
10
5
B
1
2
FPL
MSFT
55Portfolios of Assets
Capital Asset Pricing Model (CAPM)
SML2
SML1
k
20
15
Shift due to change in risk-free rate from 5 to
8. Note that all returns will increase by 3
10
5
B
1
2
MSFT
FPL