Futures Hedging Strategies and Interest Rate Futures
Read Chapters 3 and 6 in Hull
Outline
- Hedges
- Basis risk
- Optimal hedge ratio
- Hedge using index futures
- Stack and roll
- Day count conventions
- Treasury bills and bonds
- Eurodollar futures
- Convexity adjustment
- Duration
- Duration-based hedge ratio
Hedges
- You enter a long futures hedge when you know you will purchase an asset in the future and want to lock in the price
- Futures and asset refer to different things
- Long futures hedge – makes money if asset price increases and loses money if it falls
- A spot price increase will make asset more expensive to buy
- The gain of the hedge offsets the higher spot price
- You enter a short futures hedge when you know you will sell an asset in the future and want to lock in the price
- Short futures hedge – makes money if asset price drops and loses money if it increases
- A spot price decrease makes a loss when you sell it
- Gain on hedge offsets loss on a lower spot price
- Benefit of Hedging
- Companies should focus on their main business and take steps to minimize risks from interest rates, exchange rates, and other market variables
- Problems of Hedging
- Shareholders can diversify their investments and hedge to reduce risk
- Shareholds may increase their risk to hedge when competitors do not
- You could have trouble explaining a situation to your manager if the company gained on the underlying asset but lost on the hedge
- Futures prices converge to spot market
Basis Risk
- Basis risk - the value of a futures contract will not move in line with that of the underlying exposure
- Basis is the difference between spot and futures prices
- Basis = Spot price (S) – Future price (F)
- Basis risk arises from the uncertainty when the hedge is closed out
- Note – you are not buying the futures to lock in a future price
- You are buying (shorting) the future as a means to offset gains/losses on the asset's price change
- Long hedge to purchase an asset
- Define
-
F 1
: You buy futures price when you set up hedge
-
F 2
: Futures price when you sell futures to purchase asset
-
S 2
: Asset price at time of purchase
-
b 2
: Basis at time of purchase
Cost of an asset |
S 2
|
Gain on Futures |
F 2 − F 1
|
Net amount paid |
S 2 − (F 2 − F 1) = F 1 + (S 2 − F 2) = F 1 + b 2
|
Net amount received |
−S 2 + (F 2 − F 1)
|
- Company uses long hedge
- Company hedges at t 1
and buys asset at t 2
from spot market
- If basis rises (↑ S 2
or ↓ F 2
), company's position worsens
-
↑ S 2 − ( ↓ F 2 − F 1) = ↑ S 2 − ↓ hedge = F 1 + b 2 ↑
- Company must buy asset at higher price for S 2
and/or takes a loss on the hedge
- Not a complete hedge
- Short hedge to sale an asset
- Define
-
F 1
: Futures price when you set up hedge
-
F 2
: Futures price when you sell asset at time 2
-
S 2
: Asset price at time of sale
-
b 2
: Basis at time of sale
Price of an asset |
S 2
|
Gain on Futures |
F 1 − F 2
|
Net amount received |
S 2 + (F 1 − F 2) = F 1 + (S 2 − F 2) = F 1 + b 2
|
- Company uses short hedge
- Company hedges at t 1
and sells asset at
t2 on spot market
- If basis rises (↑ S 2
or ↓ F 2
), company's position improves
-
↑ S 2 + ( F 1 −↓ F 2 ) = ↑ S 2 + ↑ hedge = F 1 + b 2 ↑
- Company can sell asset at higher price for S 2
and/or takes a gain on the hedge
- Not a complete hedge
- Choice of Contract
- Choose a delivery month that is as close as possible to, but later than, the end of the life of the hedge
- If asset has no futures contract for a hedge, choose the contract whose futures price is most highly correlated with the asset price
- Basis has two components
Optimal Hedge Ratio
- Proportion of the exposure that should be hedged optimally
-
h is the minimum hedge ratio
-
σ S
is the standard deviation of ΔS, the change in the spot price during the hedging period
-
σ F
is the standard deviation of ΔF, the change in the futures price during the hedging period
-
ρ is the coefficient of correlation between ΔS and ΔF
- Optimal Number of Contracts, N*
- * means optimal number of contracts
- h* means optimal hedge ratio
-
Q A
Size of position being hedged (units)
-
Q F
Size of one futures contract (units)
- Note: Tailing adjustment is accounting for the daily settlement of futures
- That is why is uses value and not quantity
- Optimal number of contracts, N*, if no tailing adjustment
- Optimal number of contracts, N*, after tailing adjustment to allow daily settlement of futures
-
V A
Value of position being hedged, V A = S 0 x Q A
-
V F
Value of one futures contract, V F = F 0 x Q F
- Example
- Bus company will purchase 1 million gallons of diesel fuel in one month and hedges using heating oil futures
- From historical data σ F = 0.05 , σ S = 0.02 , and ρ = 0.85
-
h* = 0.850 x 0.020 / 0.050 = 0.340
- Optimal number of contracts assuming no tailing adjustment
- The size of one heating oil contract is 42,000 gallons
-
N* = 0.340 x 1,000,000 / 42,000 = 8.095
- Optimal number of contracts after tailing adjustment
- The spot price is 2.20 for diesel fuel and the futures price is 1.90 for heating oil both dollars per gallon
-
V A = 1,000,000 x 2.20 = 2,200,000
-
V F = 42,000 x 1.90 = 79,800
-
N* = 0.340 x 2,200,000 / 79,800 = 9.37
Hedging Using Index Futures
- To hedge the risk in a portfolio the number (N*) of contracts that should be shorted is
- A stock portfolio loses value when stock prices fall
- A short earns money when prices fall
- Define
-
V A
is the current value of the portfolio
-
β is the beta
-
V F
is the current value of one futures
-
V F
= futures price times contract size
- Example
- Futures price of S&P 500 is 1,500
- Size of portfolio is $10 million
- Beta of portfolio is 1.2
- One contract is on $250 times the index
- What position in futures contracts on the S&P 500 is necessary to hedge the portfolio?
-
V A = $10 million
-
V F = 1,500 ($250) = $375,000
-
N* = 1.2 x $10 million / $375,000 = 32
- You short the contracts in case the S&P 500 Index falls
- You are happy if the value of your portfolio increases
- You are not happy if the value of the portfolio falls
- The short gains when the portfolio falls in value
- What if beta changes?
- What position is necessary to reduce the β of the portfolio to 0.85?
-
V A = $10 million
-
V F = 1,500 ($250) = $375,000
-
β = 0.85
-
N* = 0.85 x $10 million / $375,000 = 22.667 (or 23 contracts)
- Long 9 contracts from the original 32
- Remember - a long unwinds a short, and vice versa
- Portfolio less sensitive to market
- What position is necessary to increase the β of the portfolio to 2.5?
-
β = 2.5
-
N* = 2.5 x $10 million / $375,000 = 66.667 (or 67 contracts)
- Short 35 additional contracts with the original 32
- Portfolio more sensitive to market
- Why Hedge Equity Returns
- May want to be out of the market for a while
- Hedging avoids the costs of selling and repurchasing the portfolio
- Suppose stocks in your portfolio have an average beta of 1.0, but you feel they have been chosen well and will outperform the market in both good and bad times
- Hedging ensures that the return you earn is the risk-free return plus the excess return of your portfolio over the market
Stack and Roll
- We can roll futures contracts forward to hedge future exposures
- Initially we enter into futures contracts to hedge exposures up to a time horizon
- Just before maturity we close them out and replace them with new contract to reflect the new exposure
- Liquidity Issues
- In any hedging situation, the hedger may experience losses on the hedge while he/she does not realize gains on the underlying exposure
- This can create liquidity problems
- For example
- Metallgesellschaft sold long term fixed-price contracts to businesses on heating oil and gasoline
- Company hedged using stack and roll
- Company went long on futures to lock in price for oil and gasoline
- The price of oil fell
- Company realized huge losses ($1.33 billion) to cover future contracts for margin calls
- Stock Picking
- If you think you can pick stocks that will outperform the market, futures contract can be used to hedge the market risk
- If you are right, you will make money whether the market goes up or down
- Rolling The Hedge Forward
- We can use a series of futures contracts to increase the life of a hedge
- Each time we switch from 1 futures contract to another we incur a basis risk
Day Count Convention
- Day Count Conventions
- Defines the period of time to which the interest rate applies
- The period of time used to calculate accrued interest relevant when the instrument is bought or sold
- Day Count Conventions in the U.S.
Treasury Bonds: |
Actual/Actual (in period) |
Corporate Bonds: |
30/360 |
Money Market Instruments: |
Actual/360 |
- Examples
- Bond: 8% Actual/ Actual in period
- 4% is earned between coupon payment dates
- Accruals on an Actual basis
- When coupons are paid on March 1 and Sept 1, how much interest is earned between March 1 and April 1?
- interest = 0.08 x 31 / 184 = 0.0135
- Count days in the month: March 31, April 30, May 31, June 30, July 31, August 31, Septermber 1
- Bond: 8% 30/360
- Assumes 30 days per month and 360 days per year
- When coupons are paid on March 1 and Sept 1, how much interest is earned between March 1 and April 1?
- Total days = 6 months * 30 = 180 days
- 30 days interest
- interest = 0.08 x 30 / 180 = 0.0133
- T-Bill: 8% Actual/360:
- 8% is earned in 360 days
- Accrual calculated by dividing the actual number of days in the period by 360
- How much interest is earned between March 1 and April 1?
- Days = 31
- Months = 180
- interest = 0.08 x 31 / 180 = 0.0138
- The February Effect
- How many days of interest are earned between February 28, 2013 and March 1, 2013 when
- Day count is Actual/Actual in period?
- Day count is 30/360?
- Solution
- Between Feb 28 and March 1 Day = 1 for actual / 365
- Under 30/360, you get 3 days
- Note – check for leap year, February 29, 2016
Treasury Bills and Bonds
- Treasury Bill Prices in the US
- P is quoted price
- Y is cash price per $100
- Face value = $100
- n: number of days
- U.S. Treasury Bond Price Quotes
-
Cash price = Quoted price + Accrued Interest
- Called dirty price
- Bond has not paid interest yet
- Buyer collects the whole coupon payment
- Prorate the accrued interest
- Note: Bond price = 70-15 = 70 + 15/32
- Remember to divide second number by 32
- Treasury Bond Futures
- The conversion factor for a bond is approximately equal to the value of the bond assuming the yield curve is flat at 6% with semiannual compounding
- Writer of futures must deliver bond
- Treasury bonds have different coupon rates and face values
- Conversion factor puts all bonds on equal footing
Cash price received by party with short position = Most Recent Settlement Price × Conversion factor + Accrued interest
- Example
- Most recent settlement price = 85.00
- Conversion factor of bond delivered = 1.45
- Accrued interest on bond =5.50
- Price received for bond is
-
price = 1.45×85.00+5.50 = $128.75 per $100 of principal
- Chicago Board of Trade (CBOT) T-Bonds & T-Notes
- Factors that affect the futures price
- Delivery can be made any time during the delivery month
- Any range of eligible bonds can be delivered
- The wild card play
- If bond prices fall after 2:00 pm on first delivery day of month
- Party with short position issues intent to deliver at 3:45 pm
- The party closes the short by buying at the cheaper price at 3:45 pm
- If price rises, the party keeps the short open
Eurodollar Futures
- A Eurodollar is a dollar deposited in a bank outside the United States
- Eurodollar futures are futures on the 3-month Eurodollar deposit rate
- Same as 3-month LIBOR rate
- One contract is on the rate earned on $1 million
- Use equation to calculate price
contract price = 10,000 × [100 − 0.25 × (100 − Q)]
- A change of one basis point or 0.01 in a Eurodollar futures quote corresponds to a contract price change of $25
- Show
- Quote (Q)
- Interest = 100 – Q
- A one basis point equates to a Q = 99.99
-
contract price = 10,000 × [100 − 0.25 × (100 − 99.99)] = 999,975
- Contract price = 999,975
- Difference = 1,000,000 – 999,975 = 25
- A Eurodollar futures contract is settled in cash
- When it expires (on the third Wednesday of the delivery month) the final settlement price is 100 minus the actual three month deposit rate
- Table below shows Eurodollar futures quotes
Date |
Quote |
Oct 1 |
96.55 |
Oct 2 |
97.11 |
Oct 3 |
95.95 |
……. |
…… |
Nov 21 |
98.65 |
- Example
- Suppose you buy (take a long position in) a contract on November 1
- The contract expires on November 21
- The table above shows the prices
- a) How much do you gain or lose on the first day?
- On Nov. 1 you invest $1 million for three months on Dec 21
- The contract locks in an interest rate
-
interest rate = 100 - 96.55 = 3.45%
- b) How much do you gain or lose on the second day?
-
interest = 97.11 – 96.55 = 0.56
- 56 basis points
-
Gain = $25 (56) = $1,400
- c) How much do you gain or lose over the whole time until expiration?
- You earn 100 – 98.65 = 1.35% on $1 million for three months
- Basis points = 98.65 (Nov. 21) – 96.55 (Oct. 1) = 2.1
- 210 basis points
- You locked in a rate of 3.45%, which equals $8,625
- The final rate is 1.35% or 135 x $25 = 3,375
-
Gain = 8,625 – 3,375 = 5,250
Convexity Adjustment
- Forward Rates and Eurodollar Futures
- Eurodollar futures contracts last as long as 10 years
- For Eurodollar futures lasting beyond two years we cannot assume that the forward rate equals the futures rate
- Two reasons explain why
- Futures is settled daily where forward is settled once
- Futures is settled at the beginning of the underlying three-month period;
- Forward Rate Agreement (FRA) is settled at the beginning of the underlying three-month period
- FRA – two parties switch interest rate payments on some amount of money
- For example, the long position party pays a fixed interest and receives a variable interest rate
- Parties settle the difference in interest rates
- A "convexity adjustment" often made is
-
T 1
is the start of period covered by the forward/futures rate
-
T 2
is the end of period covered by the forward/futures rate (90 days later that T 1
)
-
σ is the standard deviation of the change in the short rate per year
-
Forward Rate = Futures Rate − 0.5 σ 2 T 1 T 2
- Table below shows convexity adjustment for σ=0.012
Maturity of Futures |
Convexity Adjustment (bps) |
2 |
10.89 |
4 |
41.14 |
6 |
90.75 |
8 |
159.72 |
10 |
248.05 |
- Example 1
-
σ = 0.022
-
T 1 = 2
-
T 2 = 2.25 , Eurodollar contract is 3 months
-
convexity adj. = 0.5(0.022) 2(2)(2.25) = 0.001089
- Multiply by 10,000 to get number in table
- Example 2
-
σ = 0.022
-
T 1 = 10
-
T 2 = 10.25 , Eurodollar contract is 3 months
-
convexity adj. = 0.5(0.022) 2(10)(10.25) = 0.024805
Duration
- Duration of a bond that provides cash flow c i
at time t i
is
- where B is its price and y is its yield (continuously compounded)
- This leads to
- Similar to elasticity
- If the yield, y, increases by 1% or (100 bps), then the bond price falls by approximately ΔB / B percent.
- Below shows how to derive duration
- When the yield y is expressed with compounding m times per year
- The expression is referred to as the "modified duration"
- Duration Matching
- This involves hedging against interest rate risk by matching the durations of assets and liabilities
- It provides protection against small parallel shifts in the zero curve
- Using Eurodollar Futures
- One contract locks in an interest rate on $5 million for a future 3-month period
- How many contracts are necessary to lock in an interest rate on $5 million for a future six-month period?
- Two contracts
- One contract for the first 3 months
- One contract for the second 3 months
Duration-Based Hedge Ratio
- Define
-
V F
: Contract Price for Interest Rate Futures
-
D F
: Duration of Asset Underlying Futures at Maturity
-
P: Value of portfolio being Hedged
-
D P
: Duration of Portfolio at Hedge Maturity
-
N*: Number of contracts
- Example
- Three month hedge is required for a $25 million portfolio.
- Duration of the portfolio in 3 months will be 5.5 years.
- 3-month T-bond futures price is 97-13 so that contract price is $97,406.25
- Contracts with zero discount equal $100,000
- Note: 97-13 = 97 + 13/32 = 97.40625
- Duration of cheapest to deliver bond in 3 months is 8.7 years
- Number of contracts for a 3-month hedge is
- Limitations of Duration-Based Hedging
- Assumes that only parallel shift in yield curve take place
- Assumes that yield curve changes are small
- When we use T-Bond futures, we assume no changes in the cheapest-to-deliver bond
- GAP Management
- Banks use a more sophisticated approach to hedge interest rate
- They bucket the zero curve
- Divide loans and sources into buckets by maturity
- First bucket – between 0 and 1 month
- Second bucket – between 1 and 3 months
- Match the assets and liabilities for each bucket
- Hedging exposure to situation where rates corresponding to one bucket change and all other rates stay the same
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