In: Finance
You currently own $20,000 worth of IBM's stock. Suppose that IBM
has an
expected return of 15% and a volatility of 23%. The market
portfolio has
an expected return of 11% and a volatility of 16%. The risk-free
rate is 5%.
Assuming the CAPM assumptions hold, what alternative investment has
the
highest possible expected return while having the same volatility
as IBM?
What is the expected return of this portfolio?
now we have to create a portfolio consist of Market portfolio and Risk free assets.
Risk free asset have zero risk or its standard deviation or volatility is Zero.
Note- Volatility is also know as the standard deviation or risk
Standard deviation of a portfolio containing a risky asset and a non risky asset =
here, = standard deviation of the Risky asset i.e. Standard deviation of market portfolio = 16%
WA = weight of risky asset or weight of market portfolio.
hence,
23% = 16% *WA
=>WA or weight of market portfolio = 1.4375
weight of risk free asset = 1-WA = 1-1.4375 = -0.4375
it means We have to create a portfolio by-
* Buying market portfolio of = $20000* 1.4375 = $28750
* and by borrowing from risk free asset = $20000*0.4375 = $8750
in simple term we have to borrow $8750 from risk free asset and invest it in market portfolio.
Total investment in market portfolio = Amount available + amount borrowed at risk free
=>Total investment in market portfolio=$20000+$8750 = $28750
Portfolio-
Amount($) | Weight | |||
Market portfolio | Invest | $28,750 | 1.4375 |
($28750/$20000) |
Risk free asset | Borrow | -$8,750 | -0.4375 |
(-$8750/$20000) |
Total | $20,000 | 1.000 |
volatility or standard deviation of the portfolio = = 16%* 1.4375 = 23%[ Which is same as the volatility of IBM]
Expected return on the portfolio =
Return | Weight | return*weight | |
Market portfolio | 11% | 1.4375 | 15.8125 |
Risk free asset | 5% | -0.4375 | -2.1875 |
Highest possible expected return | 13.625% |
Hence highest possible portfolio return on the portfolio consist of the market portfolio and risk free asset having volatility of 23% is 13.625%.
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