Hedging Notes Cpa P15
Hedging Notes Cpa P15
Forward Contract
Options
Swaps
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✓ Difficulty in Finding Reliable Counterparty: For a swap to be executed
successfully, both parties involved must have complementary needs,
meaning they should want to exchange exact amounts of the currencies
or cash flows involved. Finding a reliable counterparty with matching
requirements can sometimes be challenging. The search for a suitable
counterparty can be time-consuming and may involve additional costs,
such as legal fees or due diligence expenses.
✓ Sovereign Risk: When engaging in swaps involving currencies of
different countries, there may be a risk of sovereign interference or
exchange controls. Governments may impose restrictions or regulations
that affect the ability to carry out the swap or the free movement of
funds
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6. In-the-money: A put or a call option is said to in-the-money when it is
advantageous for the investor to exercise it. In the case of in-the-money
call options, the exercise price is less than the current value of the
underlying asset, while in the case of the in-the-money put options, the
exercise price is higher than the current value of the underlying asset
7. Out-of-the-money: A put or a call option is out-of-the-money if it is not
advantageous for the investor to exercise it. In the case of the out-of-
the-money call options, the exercise price is higher than the current
value of the underlying asset, while in the case of the out-of-the-money
put options, the exercise price is lower than the current value of the
underlying asset.
8. At-the-money: When the holder of a put or a call option does not lose or
gain whether or not he exercises his option, the option is said to be at-
the-money. In the case of the out-of-the-money options, the exercise
price is equal to the current value of the underlying asset
Call Option
A call option on a share (or any asset) is a right but not obligation to buy the
share (underlying asset) at an agreed exercise (strike) price. Suppose that the
current share price of share is Shs 1,300. You expect that price in a 3-month
period will go up to Shs 1,500. But you do fear that the price may fall below
Shs 1,200. To reduce the chance of your risk and at the same time to have an
opportunity of making profit, instead of buying the share, you can buy a 3-
month call option on share at an agreed exercise price (E) of, say, Shs 1,250.
Will you exercise your option if the price of the share is Shs 1,500 in three
months?
You will exercise your option since you get a share worth Shs 1,500 by paying
an exercise price of Shs 1,250. You will gain Shs 250; that is, the pay-off or
the value of your call option at an expiration of Shs 250. Your call option is
in-the-money at maturity.
What will you do if the price of the share is Shs 1,200 when the call option on
share expires? Obviously, you will not exercise the option. You gain nothing.
Your call option is worthless, and out-of-the-money at expiration. You may
notice that the value of your call option can never be less than zero.
Thus, you should exercise call option when share price at expiration exceeds
exercise price. On the other hand, you should not exercise the call option
when the share price at expiration is less or equal to the exercise price.
The value of the call option at expiration is:
Value of call option at expiration = Maximum [Share price – Exercise price, 0]
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The expression above indicates that the value of a call option at expiration is
the maximum of the share price minus the exercise price or zero. The call
option holder’s opportunity to make profits is unlimited. It depends on what
the actual market price of the underlying share is when the option is
exercised. The greater the market value of the underlying asset, the larger is
the value (pay-off) of the option
Figure showing the pay-off or value of a call option.
It may be observed from Figure below that the call buyer’s potential pay-off
becomes unlimited, once the price of the share (the underlying asset) goes
beyond the exercise price. If the share price is on or below the exercise price,
the call buyer will not exercise his option. Thus, his pay-off will be zero, since
the option is worth nothing
Value of call option
It may also be observed from Figure above that the possible outcomes can be
divided into two parts: one, above the exercise price and other, below the
exercise price. The outcomes above the exercise price are said to be in-the-
money and are beneficial to the option holder but not the outcomes below the
exercise price. It is the exercise price that divides the good and bad outcomes
How is the seller (or the writer) of a call option affected when the value of the
underlying asset changes? Figure below shows his position as a mirror image
of the call buyer’s position. The call the buyers gain is called seller’s loss. The
seller of the call option will not incur any loss when the price of the share (the
underlying asset) is less than the exercise price since the buyer will not
exercise his option. However, if the share price rises and goes beyond the
exercise price, the potential loss of the call seller is very high.
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Figure showing a pay-off of call option writer (seller)
In-the-money Out-of-the-monEy
(good outcomes ) (bad outcomes) Value of share/underly ing asset
Value of call option
Exercise price
Call premium
A call buyer exercises his right only when the outcomes are favorable to him.
The seller of a call option, being the owner of the asset, gives away the good
outcomes in favor of the option buyer. The buyer of a call option must,
therefore, pay an up-front price, called call premium, to the call seller to buy
the option. The call premium is a cost to the option buyer and a gain to the
call seller. What is the net pay-off of the buyer and the seller of a call option
when the call premium (that the buyer has to pay to the seller) is involved?
Illustration of call option pay-off
The share of Pakasa Ltd is selling for Shs 10,400. An investor buys a 3 months
call option at a premium of Shs 500. The exercise price is Shs 10,500. What
is the investor’s pay-off if the share price is Shs 10,000, or Shs 10,500, or Shs
11,000, or Shs 11,500, or Shs 12,000 at the time the option is exercised?
solutions
The investor will exercise his option for any price above the exercise price Shs
10,500. Since the exercise price is Shs 10,500 and the investor (the buyer)
has to pay a premium of Shs 500, his pay-off will be zero when the share price
rises to Shs 11,000. Thus, Shs 11,000 is a break-even price (i.e., the exercise
price plus the call premium) for him. The exercise price, Shs 10,500, separates
the good outcomes from the bad outcomes. The seller of the call option (the
asset owner) is being paid the call premium, Shs 500, for giving up the good
outcomes in favour of the buyer of the call option.
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Table showing the call option holder’s pay-off at expiration
Shs Shs Shs Shs Shs
Share price 10,000 10,500 11,000 11,500 12,000
Investor's
inflows: Sale of
shares ---- --- 11,000 11,500 12,000
Investor's
outflows:
Exercise option --- --- 10,500 10,500 10,500
Call premium 500 500 500 500 500
Net pay-off -500 -500 0 500 1,000
What is the pay-off of the seller of the call option? The position of the call
option seller will be opposite to that of the buyer as shown in Table above. If
the buyer (investor) exercises his option, the seller will lose. His (seller’s)
potential loss is very high, and his profit is limited to Shs 500 (the call
premium). If Figure above is turned up side down, the call seller’s position can
be depicted graphically in table below
Table showing the call option seller’s pay-off at expiration
Shs Shs Shs Shs Shs
Share price 10,000 10,500 11,000 11,500 12,000
Seller's inflows:
Exercise option ---- --- 10,500 10,500 10,500
Call premium 500 500 500 500 500
Seller's outflows:
Share price --- --- 11,000 11,500 12,000
Net pay-off/profit 500 500 0 -500 -1,000
10
Exercise price
Pay-off
0 Share price
10,000 10,500 11,000 11,500 12,000
-5
Premium Break-even price
-10
Limited loss area
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Pay-off of call option seller
10
Pay-off
5 Break-even price
0 Share price
10,000 10,500 11,000 11,500 12,000
-5
Exercise price Unlimited loss
-10
Put Option
A put option is a contract that gives the holder a right but not an obligation
to sell a specified share (or any other asset) at an agreed exercise price, on or
before a given maturity period.
Suppose you expect price of share to fall in the near future. Therefore, you
buy a 3-month put option at an exercise price of Shs 5,000. The current
market price of a share is Shs 4,800. If the price actually falls to Shs 3,500
after three months, you will exercise your option. You will buy the share for
Shs 3,500 from the market and deliver it to the put-option seller (writer) to
receive Shs 5,000. Your gain is Shs 1,500, ignoring the put option premium,
transaction costs and taxes.
You will forgo your put option if the share price rises above the exercise price;
the put option is worthless for you and its value for you is zero. A put buyer
gains when the share price falls below the exercise price. Ignoring the cost of
buying the put option (called put premium), his loss will be zero when the
share price rises above the exercise price since he will not exercise his option.
Thus, you should exercise the put option when Exercise price is greater than
share price at expiration. On the other hand, you should not exercise the put
option when the Exercise price is less or equal to share price at expiration
The value or pay-off of a put option at expiration will be: Value of put option
at expiration = Maximum [Exercise price – Share price at expiration, 0]
Pay-off diagram for the put option buyer
The figure shows that the value of the put option for the holder depends on
the value of the underlying asset. The value of the put option is zero when it
is out-of-the-money. You may observe from diagram that the potential profit
of the put option buyer is limited, since share price cannot fall below zero.
The exercise price is again the dividing point between the good and bad
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outcomes. The put option buyer’s gain is the seller’s loss. The seller insures
the buyer from the bad outcomes.
Value of put option
Limited profit
Exercise price
In-the-money Out-of-the-money
(good outcomes) (bad outcomes)
Exercise price
Limited loss
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relative to the underlying asset price increases the intrinsic value,
making the call option more valuable and vice versa. For put options,
a higher strike price relative to the underlying asset price increases
the intrinsic value and the put option's value.
3. Volatility: Volatility refers to the degree of price fluctuations in the
underlying asset. Higher volatility generally increases the value of
options because it implies a greater potential for large price swings,
which can lead to higher profits for option holders. Increased volatility
raises the probability of the option ending up in-the-money (for both call
and put options) and thus contributes to their value.
4. Time to expiration: The time remaining until the option's expiration
affects its value. Generally, as the time to expiration decreases, the value
of the option decreases, assuming other factors remain constant. This is
because options have a limited lifespan, and the potential for favorable
price movements diminishes as the expiration approaches.
5. Risk-free Interest rates: Options depend on the interest rate that applies
to the period that matches the length of time of the option’s expiration.
For a call option, the present value of the exercise price will reduce if the
interest rate is high for a given time to expiration. This consequently
increases the value of a call option and the reverse is also true. For put
option, the value of put options tends to decrease as the risk-free interest
increases (due to lower opportunity costs).
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be predicted.
• The risk-free interest rate is constant and known: The model assumes
that the risk-free interest rate is constant over the life of the option and
is known with certainty. This assumption allows the model to discount
future cash flows to their present value at the risk-free rate.
• Normal distribution: Stock returns are normally distributed. It implies
that the volatility of the underlying asset is constant over the life of the
option and is known with certainty.
• The underlying asset price follows a log-normal distribution: The model
assumes that the price of the underlying asset follows a log-normal
distribution, which means that the logarithm of the price follows a
normal distribution
According Black-Scholes model, the value of call and put options are given as
follows:
Value of call option: C0 = S0 N(d1) – K e-r*T N(d2)
Value of put option: P0 = K e-r*T N(– d2) – S0 N(– d1)
𝐼𝑛 (𝑆/𝐾)+ (𝑟 +𝜎 2/2)𝑇
Where; d1 =
𝜎√𝑇
d2 = d1 - 𝜎√𝑇
where;
C0 = the current value of call option
P0 = the current value of put option
S0 = the current market value of the share
K = the exercise price
E = 2.7183, the exponential constant
R = the risk-free rate of interest
T = the time to expiration (in years)
N( ) = the cumulative normal probability density function
Ln = the natural logarithm
Σ = standard deviation (volatility of the underlying stock
σ2 = variance of the continuously compounded annual
return on the share.
The Black–Scholes model has two features. First, the parameters of the model,
except the share price volatility, are contained in the agreement between the
option buyer and seller. Second, in spite of its unrealistic assumptions, the
model is able to predict the true price of option reasonably well.
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Example
Mr. Mugisha is interested in writing a six-months call option on Pakasa Ltd’s
share. Pakasa share is currently selling for Shs 12,000. The volatility
(standard deviation) of the share returns is estimated as 67%. Mr. Mugisha
would like the exercise price to be Shs 12,000. The risk-free rate is assumed
to be 10%. How much premium should Mr. Mugisha charge for writing the
call option? What would be the corresponding value of the put option?
Proposed solutions
Value of call option: C0 = S0 N(d1) – K e-r*T N(d2)
𝐼𝑛 (𝑆/𝐾)+ (𝑟 +𝜎 2/2)𝑇
Where; d1 =
𝜎√𝑇
d2 = d1 - 𝜎√𝑇
12,000)+ (0.1 0.672
) 0.5
𝐼𝑛 (
+
d1 = 12,000 2
0.67 𝑥 √0.5
d1 =
𝐼𝑛 (1)+ 0.1622 = 0.34
0.4738
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d2 = 0.34 - (0.67 𝑥 √0.5)= -0.13
From the standard normal distribution table, we obtain N(d1) and N(d2) as
follows;
N(d1) = 0.6331
N(d2) = 0.4483
Value of call option: C0 = (12,000 x 0.6331) – (12,000 e-0.1*0.5 x 0.4483)
C0 = 7,597 – 5,117 = Shs 2,480
The value of corresponding put option can be computed as follows:
P0 = K e-r*T N(– d2) – S0 N(– d1)
P0 = 12,000 e-0.1*0.5 N(0.13 ) – 12,000 N(– 0.34)
P0 = 12,000 e-0.1*0.5 (0.5517) – 12,000 (0.3669)
P0 = 6,298 – 4,403 = Shs 1,895
Put-call parity
Put-call parity is a fundamental concept in option pricing theory that shows
the relationship between the prices of call and put options with the same
underlying asset, strike price, and expiration date. The theory is based on the
principle of no-arbitrage, which states that two securities with identical
payoffs must have the same price. The call parity theory is expressed as
follows:
C0 + K e-r*T = P0 + S0
Where;
• C0 is the price of a call option on an underlying asset
• K e-r*T is the present value of the strike price, K, discounted at the risk-
free rate over the expiration time
• P0 is the price of a put option on the same underlying asset, with the
same strike price and expiration date as the call option
• S0 is the current price of the underlying asset
The call parity theory suggests that the sum of the price of a call option and
the present value of its strike price is equal to the sum of the price of a put
option and the current price of the underlying asset. This relationship holds
true at any point in time before the expiration date of the options.
The intuition behind put-call parity theory is that owning a call option gives
the holder the right to buy the underlying asset at the strike price K. If the
holder exercises the option, they pay K to acquire the asset. However, they
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can also achieve the same result by selling a put option with the same strike
price K. The seller of the put option is obligated to buy the underlying asset
from the holder at the strike price K if the holder chooses to exercise the put
option. By selling the put option, the holder receives the premium and has
effectively locked in the purchase price of the underlying asset at K.
Example
Determine the value of the put option in the above example using put-call
parity formula
Using put-call parity, the value of the put option can be computed as follows;
P0 = C0 + K e-r*T - S0
Test yourself
1) Determine the price a European Call option, currently ATM with three
months maturity. The current price of the underlying stock price is Shs
12,400. The volatility for this stock is 25% annually, while the risk-free
rate is at 8%. Also calculate the price of the corresponding put option
2) You just purchased a European Put option. The strike price of the
option is Shs 15,000 and there is one year left until maturity. The
current price of the underlying stock price is Shs 12,500. The volatility
for this stock is 45% annually, while the risk-free rate is at 10%.
Calculate the value of put option under the Black-Scholes framework
3) Determine the price a European put option. The strike price of this
option is Shs 3,500, with the current stock price at Shs 3,250. The risk-
free rate is 9% and the option will expire in 18 months. The volatility for
this stock is 45% annually.
Limitations of the Black-Scholes-Merton Model
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free interest rate throughout the option's life. However, interest rates
can change over time, and the assumption of a constant rate may not
hold in practice. Changes in interest rates can affect the pricing of
options, particularly those with longer maturities.
• Constant volatility assumption: The model assumes that volatility
remains constant throughout the option's life. However, volatility is
known to be dynamic and can change over time, particularly in
response to market events or news. This assumption may lead to
inaccuracies in pricing options, especially for longer-dated options or
during periods of high market volatility.
• Assumption of a frictionless market: Trading generally comes with
transaction costs such as brokerage fees, commission, etc. However,
the Black Scholes model assumes a frictionless market, which means
that there are no transaction costs. It is hardly ever the reality in the
trading market.
• No dividends or cash flows: The Black-Scholes model assumes that the
underlying asset does not pay any dividends or generate cash flows
during the option's life. In reality, many assets, such as stocks, do pay
dividends, which can have a significant impact on option pricing.
Adjustments need to be made to the model to account for dividend
payments.
• Assumption of normal and log normal distribution: The Black-Scholes
model assumes that stock price movements follow a log-normal
distribution and stock returns follow a normal distribution, implying
symmetric returns and no significant skewness or fat tails. However,
empirical evidence suggests that asset price returns often exhibit
skewness and fat-tailed distributions, which the model does not fully
capture.
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APPLICATION OF OPTION PRICING THEORY IN INVESTMENT DECISIONS
Introduction
The NPV analysis discussed earlier does not recognize the value of investing
in a project that can more easily adapt to changes in a company’s environment
after the decision to invest has been made. This strategic flexibility is valuable,
and this value is often not captured by the traditional NPV analysis. This leads
to some potentially value-adding investments being rejected.
It is possible to picture this strategic flexibility as a series of choices or options
that are available to managers.
In this chapter we shall see how Black-Scholes model can be adapted to value
real choices or real options that an investment decision may possess
Another benefit of this approach is that risk and uncertainties are viewed as
opportunities, where the upside outcomes can be exploited and the downside
risk can be managed.
The value of real option can then be added to the traditional NPV to give a
revised and more accurate assessment of the value created by the project
Different types of real options
1) Option to expand
Making an investment now, in addition to the cash flows created by that
investment, sometimes create an opportunity for a company to expand in
future. An option to expand can result from being able to apply the new
technology or brand name to other projects if the initial project is successful.
It can simply relate to the option to following on from a successful initial
investment by further expansion in that same area.
To be considered an option to expand, the expansion opportunity would need
to link to the initial investment i.e. the company would not be able to expand
successfully if it had not made the investment in the initial project. An option
to expand involves choosing to spend more money to exploit the upside risk
2) Option to delay
Making an investment now can, in addition to the cash inflows created by the
investment, sometimes create an opportunity for the company to reduce
further spending where an investment can potentially be delayed in a way that
adds value to the project. For projects that have a series of clearly identifiable
stages, managers may be able consider the option to delay at each stage.
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An option to delay will exist if the project is protected for example by a patent
or a license, so that the competitors are unable to exploit the investment
opportunity. For example, an option to wait may be considered to exist where
an investment starts by establishing a patent, because after securing this, a
company can then wait to see how the market conditions develop before
deciding on when to start commercial production of the product. An option to
delay involves choosing to defer the decision spend more money
3) Option to redeploy
An investment can sometimes contain an opportunity for a company to easily
redeploy assets to another use if the initial investment is not successful. An
option to redeploy involves changing the use of assets to create different
revenue stream, to manage the downside risk
4) Option to withdraw
An investment can sometimes contain a feature that gives a company a choice
or option to withdraw from the market. This would mean that the project
creates a right to selling a license or patent to a competitor or to a joint venture
partner. An option to withdraw involves choosing to raise money by
abandoning the project, to manage the downside risk
d2 = d1 - 𝜎√𝑇
where;
S0 = Present value of cash flows after exercising the option
K = Cost of the investment
R = the risk-free rate of return
T = the time to expiry of the option in years
Σ = the standard deviation of the project
When you input the variables into the formula, you should note the following;
✓ S0 is the present value of cash flows generated after exercising the
option. So, if you are told the cost of exercising an option to expand in
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three years’ time is say Shs 100m and that this follow-on project is
expected to give an NPV in three years’ time of Shs 20m. Then the value
of S0 is Shs 120m (100m+20m), discounted back by three years at the
cost of capital that was used for the project
✓ K is the cost of exercising the option. This is not discounted back to the
present value. This is because in the formula valuing a call option, E is
multiplied by e-rt which is a type of discount factor. So, if you are told
the cost of exercising an option to expand in three years’ time is say Shs
100m and that this follow-on project is expected to give an NPV in three
years’ time of Shs 20m, then the value of E is Shs 100m
✓ rf is the risk-free rate of return, this is not the same as the cost of capital
of the company
✓ t is the time to expiry of the option, not of the project. So if you
considering an option to expand in three years’ time, and this project
lasts for 5 years, then t=3 (because this is when the option to expand
must be exercised)
✓ s is the standard deviation; you may have to calculate this as the square
root of variance
valuing a call option
Test yourself 1
Project 1 has a net present value of (Shs 10m). It will also develop an expertise
so that the company would be ready to penetrate the European market with
an improved product in four years’ time. The expected cost of the investment
in four years’ time is Shs 600m.
Currently the European project is valued at zero NPV nut management
believes that economic condition in four years’ time may change and the NPV
could be positive
The standard deviation is 30%, risk-free rate is 4% and the cost of capital is
10%
Required: Evaluate the value of this option to expand
Test yourself 2
ABC Ltd is a Ugandan based company located in Kampala. The company is
considering opening a new store in Northern region to exploit the available
business opportunity in the region. The new investment is estimated to cost
Shs 120m and generate a present value of cash receipt of Shs 100m.
These figures would suggest that the investment should be rejected. However,
if the first store is opened, then the company would gain the option to open
the second store (an option to expand or follow-on). Suppose this would have
the following details:
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Time (t) 5 years’ time
Estimated cost Shs 200m
Present value of net cash receipts Shs 150m
Volatility of cash flows (σ) 28%
Risk-free rate of return 6%
Required: Evaluate the value of this option to expand
Note that the option to delay is also a call option and should be valued in the
same way as the option to expand
Valuing a put option
Test yourself 5
Company X is considering an investment in a joint venture to develop high
quality office blocks to be let out to corporate clients. This project has a 30-
year life and is expected to cost Shs 900m and to generate an NPV of Shs
100m for company X.
The project manager has argued that this understates the true value of the
project because the NPV of Shs 100m ignores the option to sell company X ‘s
share back to its partner for Shs 400m at any time after the first ten years of
the project.
The standard deviation of the project is 45% and the risk-free rate is 5% per
year
Required: Ascertain the value of this option
Test yourself 6
An online DVD and CD retailer is considering investing Shs 20m on improving
its customer information and online ordering systems. The expectation is that
this will enable the company to expand by extending its range of products. A
decision will be made in one year’s time, when the directors have had a chance
to analyze the customer behavior competitors’ businesses in more details, to
assess whether the expansion is worthwhile
Preliminary estimates of the expansion programme have found that an
investment of Shs 50m in one year’s time will generate net receipt with a
present value of Shs 40m in the years thereafter. The project’s cash flows are
expected to be quiet volatile, with a standard deviation of 40%. The current
risk-free rate of interest is 5%
Required:
Advise the firm whether the initial investment in updating the systems is
worthwhile
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Test yourself 7
A firm is considering a project that is expected to cost Shs 50m. The project,
on an average, will generate after-tax cash flows of Shs 7.5m per annum over
its estimated economic life of 15 years. The firm’s cost of capital is 15%, and
the risk-free rate is 8%. The firm thinks that the cash flows will fluctuate and
variance of the value of the cash flows will be 0.0676. As an alternative to
taking up the project now, it is thinking of delaying the project.
Required: Advise the firm on what they should do?
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