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risk management
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Introduction to Market Risk Measurement
INTF 6010 – Lecture 2
Market Risk
• Market Risk – is the risk of loss
due to movements in market factors
such as interest rates, exchange
rates, equity and commodity prices
• Market risk can affect instruments
and portfolios that contain bonds or
other fixed income instruments,
equities, foreign exchange positions
or instruments, derivatives,
commodity positions, structured
products.
Notes
Fixed Income
• Fixed income instruments or bonds
are a form of debt.
• The price of a bond is the present
value of all its future cash-flows
• The formula below shows that price
(P) is a function of yield (y)
Ct represents cash-flows (Principal or interest)in period t
t represents the number of periods(e.g. half years) to each payment
T is the number of periods to final maturity
y is the discounting factor per period (e.g. ys/2)
T
t
t
y
CP t
1 )1(
The chart below shows the relationship between Price and
Yield for a fixed income instrument and one with an option.
Price Yield Relationship
Market Risk – Fixed Income
• Fixed income risk arises from
potential movements in the level of
volatility of the risk factors,
usually taken as bond yields.
• Movements in yields reflect economic
fundamentals.
• The primary factor in determining
the level of interest rates is
inflationary expectations.
• For corporate and agency bonds or
foreign currency sovereign bonds
Credit Spread risk is another factor
that affects bond yields.
Notes
Bond Sensitivity Measures
• Two common derivatives of the price-
yield function are Duration and
Convexity
• Duration and Convexity are the first
and second derivatives of the price
yield function
• From a mathematical perspective:
– Duration represents a tangent to the
price yield function
– Convexity represents the curvature of
the price yield function
Notes
Duration
• Duration represents an average of
the time to wait for all cash-flows
• Duration is a measure of the
interest rate sensitivity of a bond.
• Duration and modified duration are
calculated using the formulas:
)1(*
/1 )1(
y
DD
PtC
DT
tt
t
y
Ct represents cash-flows (Principal or interest)in period t
t represents the number of periods(e.g. half years) to each payment
T is the number of periods to final maturity
y is the discounting factor per period (e.g. ys/2)
P is the price of the bond
Convexity
• Convexity can be used together with
duration to give the full impact of
interest rate changes on the price
of a bond
• Convexity is calculated as follows:
PCtt
CT
ttt
y/
)1(
12
)1(
Ct represents cash-flows (Principal or interest)in period t
t represents the number of periods(e.g. half years) to each payment
T is the number of periods to final maturity
y is the discounting factor per period (e.g. ys/2)
P is the price of the bond
The Duration and Convexity Effect
• The duration effect can be
summarized as follows:
• Duration represents the percentage
change in value of a bond from a 100
basis point (1%) change in yield.
• The combined duration and convexity
effects are as follows:
Convexity actually reduces the duration impact.
yPDPP 00 *
2021
00 * yCPyPDPP
Duration and Convexity
• Duration of a Zero Coupon instrument
is the same as its time to maturity.
• The duration of a floating rate
instrument is the time to the next
coupon reset.
• The duration of a callable bond is
calculated using the call date as
the maturity date.
• Convexity is always positive for
regular coupon paying instruments.
• All else equal duration and
convexity both increase for longer
maturities, lower coupons and lower
yields .
Notes
Market Risk - Equities
• Equity holders make returns from the
appreciation in price and payment of
dividends.
• Both price movement and dividend
payments are dependent on the
performance of the company.
• There are also preferred stocks
(preference shares) where the
dividend payments are fixed i.e.
specific rate and dates
Notes
Market Risk - Equities
• Equity Risk arises from potential
movements in the value of stock
prices
• Equity Risk can be decomposed into:
– Market wide Risk
– Stock specific Risk
• Volatility can be used as a measure
of the risk of a stock or stock
index
• Value at risk (VaR) can also be
calculated for a stock or portfolio
of equities.
Market Risk - Currencies
• Foreign Exchange (FX) or currency
market is the most actively traded
in the world.
• FX trading consists of Spot
Transactions, Forward Contract and
Currency Swaps.
• Currency conversion rates are
typically quoted in European Terms
i.e. units of the currency per US
dollar.
• The exceptions to this convention
are the British Pound and the Euro
which are quoted in American Terms
i.e. units of US dollar per unit of
foreign currency.
Notes
Market Risk - Currencies
• Currency risk arises from potential
movements in the value of foreign
exchange rates.
• This can occur in the following
situations:
– Pure Currency Float where market
demand and supply determine FX rate
movements
– Fixed Currency System where rates are
subject to one off adjustments
(devaluations or revaluations).
– Change in currency regime where a
fixed currency system is changed to
floating or vice versa.
See example 11.3 on pg 263
Market Risk - Currencies
• The risk associated with spot
transactions can be measured using
volatilities and value at risk
(VaR).Exercise – analyze the currency swap on pgs 264 – 266.
Market Risk - Commodities
• Commodities typically involve the
trading of contracts on:
– Agricultural Products e.g. wheat,
corn
– Livestock and meats e.g pork bellies
– Base Metals e.g. copper, aluminum
– Precious Metals e.g. gold, silver,
platinum
– Energy Products e.g. crude oil,
natural gas
• Commodity contracts include Spot,
Futures and Options on Futures.
Notes
Market Risk - Commodities
Important concepts:
• Convenience Yield – benefit of
holding an inventory of a commodity
that is used in production.
• Lease Rate – When a commodity can be
lent out for profit.
• Contango – When the futures price of
a commodity is higher than the spot
price.
• Backwardation – when the spot price
is higher than the futures price.
If the lease rate on a commodity is ‘y’ and the risk free market interest rate is ‘r’ then:Contango occurs when y<rBackwardation occurs when y>r
Market Risk - Commodities
• Commodity Risk arises from potential
movements in the value of commodity
prices.
• Volatility, correlations and value
at risk can be calculated for
commodity contracts.
• Energy commodities are more volatile
than other commodities since they
are less storable than metals and as
a result are more affected by
variations in demand and supply.
See Example 11.8 on pg 273
Portfolio Sensitivity Measures
• All of the concepts covered above
can be applied a portfolio level
– Portfolio Duration and Convexity can
be found by calculating the weighted
average.
Wi represents the weight of each security in the portfolio
See examples 6.15 and 6.16 on pg 150
N
iiip
N
tiiP
wCC
wDD
1
1
**
Portfolio Sensitivity Measures
• Portfolio volatility can be
calculated using the following:
• Correlations among the assets in the
portfolio is also very important. A
portfolio of assets that is highly
correlated will tend to move up and
down together. Correlation matrices
can be used to determine the
correlation among securities.
w represents the matrix of weights
Sigma represents the covariance matrix.
wwp '2
Derivatives
• A Derivative instrument is a private
contract that derives its value from
some underlying asset price, rate or
index such as a stock, bond,
currency or commodity.
• Derivatives can be traded in private
over the counter (OTC) markets or on
organized exchanges
• The most common derivatives include
Forward Contracts, Futures
Contracts, Swaps and Options
Notes
Forward Contracts
• Forward contracts are contracts to
buy or sell an asset, currency or
commodity at a specified time in the
future.
• Example: A corn farmer can enter
into a forward contract today to
sell corn at a specified price for
delivery in the future.
• Forward contracts are contracts
between parties and typically do not
involve a clearinghouse. This gives
rise to counterparty risk.
Forward Contracts
• The valuation of a forward contracts
can be calculated using the
following:
contractin units
ofnumber or quantity n
rate freerisk
foreignor yield dividend *r
rate freerisk current r
priceasset g UnderlyinK
Contract of ValueCurrent V
Price ForwardCurrent F
PriceSpot Current S
t-T
Delivery of Time T
TimeCurrent t
t
t
t
rt
rrt
rrtt
rt
rt
tr
t
tr
t
eKFKeeFKeeSV
eSeF
DPVSeF
SeF
)(
)(
*
*
Futures Contracts
• Futures are very similar to Forward
contracts in that they both allow
the ability to buy or sell something
using a price determined today but
executed at a date in the future.
• The key differences with Futures
include:
– Trades on organized exchanges
– Standardization i.e. fixed contact
sizes and limited expiration dates
– A Clearinghouse assumes the
counterparty risk
– Marked to Market Daily
– Margins are required
Valuation of Futures are done with the same formulas as Forward Contracts.
Swaps
• Swaps are OTC agreements to exchange
a series of cash-flows according to
pre-specified terms.
• Swaps are typically longer in tenor
than Forwards or Futures.
• Common Swaps include:
– Interest Rate
– Currency
– Credit Default Swaps (CDS)
– Commodity
– Total Return etc.
Review:Interest Rate Swap pg 239Currency Swap Pg 264
To be discussed in class
The diagram below shows the a typical interest rate swap
structure where
Interest Rate Swap Structure
The diagram below shows the a typical credit default swap
structure
Credit Default Swap
Options
• Options are instruments that gives a
holder the right (but not the
obligation) to buy or sell an asset
at a specific price (strike price)
usually on a specific date.
• Options to buy are called Call
Options while options to sell are
called Put Options.
• European Options can only be
exercised at maturity while American
Options can be exercised at anytime
before or at maturity.
Common notations:
Option Premium
Strike price or exercise price
Long or short (i.e. buy or sell)
Call and Put Options
• The two most common options are call
and put options
• Call option gives the buyer the
right to buy and asset while a Put
option gives the buyer the ability
to sell an asset.
• Holding a short position (i.e. you
sold options) then you become
obligated to buy or sell the asset
if the buyer exercises the option.
Notes
Payoff on Options
• The payoff profile of a long
position in a call option is:
• The payoff profile of a long
position in a put option is:
• From the payoff profiles when is it
best to use call and put options?
)0,( Ktt SMaxC
Ct = Value of the Call option
Pt = Value of the Put option
St = Current price of the asset
K= strike price of the option )0,( tt SKMaxP
Payoff for a Long Call
Combining Options
• Combinations of call and put options
to create various kinds of payoff
profiles.
• A long position in a call option
plus a short position in a put
option in the same asset with the
same strike price and maturity dates
is equivalent to a long position in
the underlying asset.
• Other payoff structures include
Straddles, Bull Spread, Bear Spread,
Butterfly Spread etc.
See pages 183 to 185 for more option combinations
Combining Options
• The link in the relationship between
the value of a call and put option
is known as Put-Call Parity. The
relationship can be expressed as:
• This works well for European options
but does not hold exactly fro
American Options as there is the
possibility of early exercise.
Put-Call Parity is demonstrated on table 8.1 on pg 181
rrrpc eKFKeSe )(*
General Relationships
• The value of an option consists of
two components:
– The Intrinsic Value which is the
value if exercised today.
– The Time Value which is the portion
of the option premium that is
attributable to the amount of time
remaining until the expiration of the
option contract.
Notes
General Relationships
Some other general option terminology:
• At-the-money – when the current spot
price is close to the strike price
• In-the-money – when the intrinsic
value is large
• Out of the money – when the spot
price is much lower than the strike
price
Notes
Upper and Lower Bounds
• The following are some general
bounds for European options:
• If these do not hold then there will
be arbitrage opportunities.
A American Call Option on a non-dividend paying stock should never be exercised early
An American Put Option on a non dividend paying stock may be exercised early
tr
t
tt
rtt
SCt
SKep
KPp
KeSc
c tt
Caps and Floors
• A cap is a call option on interest
rates with value:
• A floor is a put option on interest
rates with value:
• A Collar is a combination of buying
a cap and selling a floor.
Notes
]0,[ KiMaxC TT
]0,[ TT iKMaxP
Introduction to VaR
• Value at Risk or VaR was developed
to measure how much an investor
could lose on an investment over a
specified horizon with a specific
probability.
• It addresses the shortcomings in
other sensitivity measure such as
Duration.
• While sensitivity measures such as
Duration are useful they do not give
a probability of occurrence and
cannot be combined for different
types of assets.
Value at Risk
• VaR provides one number that that
aggregates the risks across the
whole portfolio, taking into account
leverage, diversification and
providing a risk measure with an
associated probability.
• VaR is defined as the worst expected
loss over a target horizon under
normal market conditions at a given
confidence level.
VaR is usually expressed as a dollar loss.
Visual Representation of VaR
Steps in Calculating VaR
1. Mark to market of the security or
portfolio
2. Measure the variability of the risk
factors (e.g. standard deviation of
returns)
3. Set the time horizon or holding
period.
4. Set the confidence level.
5. Calculate and report the worst case
loss using the information above
(e.g. $7 million VaR)
Notes
Steps in Calculating VaR
• The general VaR formula is as
follows:
• For bonds the VaR formula is as
follows:
• Basel 2 recommends a 10 day VaR at
99% confidence level as the Market
Risk Charge.
There are three dominant VaR Methods:
Parametric
Historical
Monte Carlo
teMarketValuVaR
IncreaseWorstYieldMDurationeMarketValuVaR
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