Futures and Options on Foreign Exchange 7 Chapter Seven Chapter Objective: This chapter discusses exchange-traded currency futures contracts, options contracts, and options on currency futures. 7-0 Chapter Outline Futures Contracts: Preliminaries Currency Futures Markets Basic Currency Futures Relationships Eurodollar Interest Rate Futures Contracts Options Contracts: Preliminaries Currency Options Markets Currency Futures Options 7-1 Chapter Outline (continued) Basic Option Pricing Relationships at Expiry American Option Pricing Relationships European Option Pricing Relationships Binomial Option Pricing Model European Option Pricing Model Empirical Tests of Currency Option Models 7-2 Futures Contracts: Preliminaries A futures contract is like a forward contract: A futures contract is different from a forward contract: 7-3 It specifies that a certain currency will be exchanged for another at a specified time in the future at prices specified today. Futures are standardized contracts trading on organized exchanges with daily resettlement through a clearinghouse. Futures Contracts: Preliminaries Standardizing Features: Contract Size Delivery Month Daily resettlement Initial performance bond (about 2 percent of contract value, cash or T-bills held in a street name at your brokerage). 7-4 Daily Resettlement: An Example Consider a long position in the CME Euro/U.S. Dollar contract. It is written on €125,000 and quoted in $ per €. The strike price is $1.30; the maturity is 3 months. At initiation of the contract, the long posts an initial performance bond of $6,500. The maintenance performance bond is $4,000. 7-5 Daily Resettlement: An Example Recall that an investor with a long position gains from increases in the price of the underlying asset. Our investor has agreed to BUY €125,000 at $1.30 per euro in three months time. With a forward contract, at the end of three months, if the euro was worth $1.24, he would lose $7,500 = ($1.24 – $1.30) × 125,000. If instead at maturity the euro was worth $1.35, the counterparty to his forward contract would pay him $6,250 = ($1.35 – $1.30) × 125,000. 7-6 Daily Resettlement: An Example With futures, we have daily resettlement of gains an losses rather than one big settlement at maturity. Every trading day: if the price goes down, the long pays the short if the price goes up, the short pays the long After the daily resettlement, each party has a new contract at the new price with one-dayshorter maturity. 7-7 Performance Bond Money Each day’s losses are subtracted from the investor’s account. Each day’s gains are added to the account. In this example, at initiation the long posts an initial performance bond of $6,500. The maintenance level is $4,000. 7-8 If this investor loses more than $2,500 he has a decision to make: he can maintain his long position only by adding more funds—if he fails to do so, his position will be closed out with an offsetting short position. Daily Resettlement: An Example Over the first 3 days, the euro strengthens then depreciates in dollar terms: Settle $1.31 $1.30 $1.27 Gain/Loss Account Balance $1,250 = ($1.31$7,750 – $1.30)×125,000 = $6,500 + $1,250 –$1,250 $6,500 –$3,750 $2,750 + $3,750 = $6,500 On third day suppose our investor keeps his long position open by posting an additional $3,750. 7-9 Daily Resettlement: An Example Over the next 2 days, the long keeps losing money and closes out his position at the end of day five. Settle Gain/Loss $1.31 $1.30 $1.27 $1.26 $1.24 $1,250 –$1,250 –$3,750 –$1,250 –$2,500 7-10 Account Balance $7,750 $6,500 $2,750 + $3,750 = $6,500 $5,250 = $6,500 – $1,250 $2,750 Toting Up At the end of his adventures, our investor has three ways of computing his gains and losses: Sum of daily gains and losses – $7,500 = $1,250 – $1,250 – $3,750 – $1,250 – $2,500 Contract size times the difference between initial contract price and last settlement price. – $7,500 = ($1.24/€ – $1.30/€) × €125,000 Ending balance on account minus beginning balance on account, adjusted for deposits or withdrawals. – $7,500 = $2,750 – ($6,500 + $3,750) 7-11 Daily Resettlement: An Example Settle Gain/Loss Account Balance $1.30 –$– $6,500 $1.31 $1,250 $7,750 $1.30 –$1,250 $6,500 $1.27 –$3,750 $2,750 + $3,750 $1.26 –$1,250 $5,250 $1.24 –$2,500 $2,750 Total loss = – $7,500 = ($1.24 – $1.30) × 125,000 = $2,750 – ($6,500 + $3,750) 7-12 Currency Futures Markets The Chicago Mercantile Exchange (CME) is by far the largest. Others include: 7-13 The Philadelphia Board of Trade (PBOT) The MidAmerica Commodities Exchange The Tokyo International Financial Futures Exchange The London International Financial Futures Exchange The Chicago Mercantile Exchange Expiry cycle: March, June, September, December. Delivery date third Wednesday of delivery month. Last trading day is the second business day preceding the delivery day. CME hours 7:20 a.m. to 2:00 p.m. CST. 7-14 CME After Hours Extended-hours trading on GLOBEX runs from 2:30 p.m. to 4:00 p.m dinner break and then back at it from 6:00 p.m. to 6:00 a.m. CST. The Singapore Exchange offers interchangeable contracts. There are other markets, but none are close to CME and SIMEX trading volume. 7-15 Reading Currency Futures Quotes OPEN HIGH LOW SETTLE CHG OPEN INT .0028 .0025 172,396 2,266 Euro/US Dollar (CME)—€125,000; $ per € Mar Jun 1.4748 1.4737 1.4830 1.4818 1.4700 1.4693 1.4777 1.4763 Closing price Expiry month Daily Change Opening price Lowest price that day Number of open contracts Highest price that day 7-16 Basic Currency Futures Relationships Open Interest refers to the number of contracts outstanding for a particular delivery month. Open interest is a good proxy for demand for a contract. Some refer to open interest as the depth of the market. The breadth of the market would be how many different contracts (expiry month, currency) are outstanding. 7-17 Reading Currency Futures Quotes OPEN HIGH LOW SETTLE CHG OPEN INT .0028 .0025 172,396 2,266 Euro/US Dollar (CME)—€125,000; $ per € Mar Jun 1.4748 1.4737 1.4830 1.4818 1.4700 1.4693 1.4777 1.4763 Notice that open interest is greatest in the nearby contract, in this case March, 2008. In general, open interest typically decreases with term to maturity of most futures contracts. 7-18 Basic Currency Futures Relationships OPEN HIGH LOW SETTLE CHG OPEN INT .0028 .0025 172,396 2,266 Euro/US Dollar (CME)—€125,000; $ per € Mar Jun 1.4748 1.4737 1.4830 1.4818 1.4700 1.4693 1.4777 1.4763 The holder of a long position is committing himself to pay $1.4777 per euro for €125,000—a $184,712.50 position. As there are 172,396 such contracts outstanding, this represents a notational principal of over $31.8 billion! 7-19 Reading Currency Futures Quotes OPEN HIGH LOW SETTLE CHG OPEN INT .0028 .0025 172,396 2,266 Euro/US Dollar (CME)—€125,000; $ per € Mar Jun 1.4748 1.4737 1.4830 1.4818 1.4700 1.4693 1.4777 1.4763 Recall from chapter 6, our interest rate parity condition: 1 + i$ F($/€) = 1 + i€ S($/€) 7-20 Reading Currency Futures Quotes OPEN HIGH LOW SETTLE CHG OPEN INT .0028 .0025 172,396 2,266 Euro/US Dollar (CME)—€125,000; $ per € Mar Jun 1.4748 1.4737 1.4830 1.4818 1.4700 1.4693 1.4777 1.4763 From March to June 2008 we should expect lower interest rates in dollar denominated accounts: if we find a higher rate in a euro denominated account, we may have found an arbitrage. 7-21 Options Contracts: Preliminaries An option gives the holder the right, but not the obligation, to buy or sell a given quantity of an asset in the future, at prices agreed upon today. Calls vs. Puts 7-22 Call options gives the holder the right, but not the obligation, to buy a given quantity of some asset at some time in the future, at prices agreed upon today. Put options gives the holder the right, but not the obligation, to sell a given quantity of some asset at some time in the future, at prices agreed upon today. Options Contracts: Preliminaries European vs. American options 7-23 European options can only be exercised on the expiration date. American options can be exercised at any time up to and including the expiration date. Since this option to exercise early generally has value, American options are usually worth more than European options, other things equal. Options Contracts: Preliminaries In-the-money At-the-money The exercise price is less than the spot price of the underlying asset. The exercise price is equal to the spot price of the underlying asset. Out-of-the-money 7-24 The exercise price is more than the spot price of the underlying asset. Options Contracts: Preliminaries Intrinsic Value The difference between the exercise price of the option and the spot price of the underlying asset. Speculative Value The difference between the option premium and the intrinsic value of the option. Option Premium 7-25 = Intrinsic Value + Speculative Value Currency Options Markets PHLX HKFE 20-hour trading day. OTC volume is much bigger than exchange volume. Trading is in six major currencies against the U.S. dollar. 7-26 PHLX Currency Option Specifications Currency Australian dollar British pound Canadian dollar Euro Japanese yen Swiss franc Contract Size AD10,000 £10,000 CAD10,000 €10,000 ¥1,000,000 SF10,000 http://www.phlx.com/products/xdc_specs.htm 7-27 Basic Option Pricing Relationships at Expiry At expiry, an American call option is worth the same as a European option with the same characteristics. If the call is in-the-money, it is worth ST – E. If the call is out-of-the-money, it is worthless. CaT = CeT = Max[ST - E, 0] 7-28 Basic Option Pricing Relationships at Expiry At expiry, an American put option is worth the same as a European option with the same characteristics. If the put is in-the-money, it is worth E - ST. If the put is out-of-the-money, it is worthless. PaT = PeT = Max[E – ST, 0] 7-29 Basic Option Profit Profiles Profit Owner of the call If the call is in-themoney, it is worth ST – E. Long 1 call If the call is out-ofthe-money, it is worthless and the –c0 buyer of the call loses his entire investment of c0. loss 7-30 ST E + c0 E Out-of-the-money In-the-money Basic Option Profit Profiles Profit Seller of the call If the call is in-themoney, the writer loses ST – E. If the call is out-ofc0 the-money, the writer keeps the option premium. ST E + c0 E loss 7-31 Out-of-the-money In-the-money short 1 call Basic Option Profit Profiles Profit If the put is inthe-money, it is E – p 0 worth E – ST. The maximum gain is E – p0 If the put is outof-the-money, it is worthless and – p0 the buyer of the put loses his entire investment of p0. loss 7-32 Owner of the put ST E – p0 long 1 put E In-the-money Out-of-the-money Basic Option Profit Profiles If the put is inthe-money, it is worth E –ST. The maximum loss is – E + p0 Profit p0 If the put is outof-the-money, it is worthless and the seller of the put keeps the option premium – E + p0 of p0. loss 7-33 Seller of the put ST E – p0 E short 1 put Example Profit Consider a call option on €31,250. Long 1 call on 1 pound The option premium is $0.25 per € The exercise price is $1.50 per €. –$0.25 ST $1.75 $1.50 loss 7-34 Example Profit Consider a call option on €31,250. Long 1 call on €31,250 The option premium is $0.25 per € The exercise price is $1.50 per €. –$7,812.50 ST $1.75 $1.50 loss 7-35 Example Profit What is the maximum gain on this put option? $42,187.50 = €31,250×($1.50 – $0.15)/€ $42,187.50 Consider a put option on €31,250. The option premium is $0.15 per € At what exchange rate do you break even? ST –$4,687.50 $1.35 The exercise price is $1.50 per euro. loss 7-36 $1.50 Long 1 put on €31,250 $4,687.50 = €31,250×($0.15)/€ American Option Pricing Relationships With an American option, you can do everything that you can do with a European option AND you can exercise prior to expiry— this option to exercise early has value, thus: CaT > CeT = Max[ST - E, 0] PaT > PeT = Max[E - ST, 0] 7-37 Market Value, Time Value and Intrinsic Value for an American Call Profit The red line shows the payoff at maturity, not profit, of a call option. Long 1 call Note that even an outof-the-money option has value—time value. Intrinsic value Time value Out-of-the-money loss 7-38 In-the-money E ST European Option Pricing Relationships Consider two investments 1 Buy a European call option on the British pound futures contract. The cash flow today is –Ce 2 Replicate the upside payoff of the call by Borrowing the present value of the dollar exercise price of the call in the U.S. at i$ 1 E The cash flow today is (1 + i$) 2 Lending the present value of ST at i£ The cash flow today is 7-39 – ST (1 + i£) European Option Pricing Relationships When the option is in-the-money both strategies have the same payoff. When the option is out-of-the-money it has a higher payoff than the borrowing and lending strategy. Thus: ST E Ce > Max (1 + i ) – (1 + i ) , 0 £ $ 7-40 European Option Pricing Relationships Using a similar portfolio to replicate the upside potential of a put, we can show that: Pe > Max 7-41 E ST – ,0 (1 + i$) (1 + i£) A Brief Review of IRP Recall that if the spot exchange rate is S0($/€) = $1.50/€, and that if i$ = 3% and i€ = 2% then there is only one possible 1-year forward exchange rate that can exist without attracting arbitrage: F1($/€) = $1.5147/€ 0 1. Borrow $1.5m at i$ = 3% 2. Exchange $1.5m for €1m at spot 3. Invest €1m at i€ = 2% 7-42 1 4. Owe $1.545m $1.5147 F1($/€) = €1.00 5. Receive €1.02 m Binomial Option Pricing Model Imagine a simple world where the dollar-euro exchange rate is S0($/€) = $1.50/€ today and in the next year, S1($/€) is either $1.875/€ or $1.20/€. S0($/€) S1($/€) $1.875 $1.50 7-43 $1.20 Binomial Option Pricing Model A call option on the euro with exercise price S0($/€) = $1.50 will have the following payoffs. By exercising the call option, you can buy €1 for $1.50. If S1($/€) = $1.875/€ the option is in-the-money: S0($/€) $1.50 7-44 S1($/€) $1.875 C1($/€) $.375 …and if S1($/€) = $1.20/€ the option is out-of-the-money: $1.20 $0 Binomial Option Pricing Model We can replicate the payoffs of the call option. By taking a position in the euro along with some judicious borrowing and lending. S0($/€) S1($/€) $1.875 C1($/€) $.375 $1.50 7-45 $1.20 $0 Binomial Option Pricing Model Borrow the present value (discounted at i$) of $1.20 today and use that to buy the present value (discounted at i€) of €1. Invest the euro today and receive €1 in one period. Your net payoff in one period is either $0.675 or $0. S0($/€) S1($/€) debt portfolio C1($/€) $1.875 – $1.20 = $.675 $.375 $1.50 7-46 $1.20 – $1.20 = $0 $0 Binomial Option Pricing Model The portfolio has 1.8 times the call option’s payoff so the portfolio is worth 1.8 times the option value. $.675 1.80 = $.375 S0($/€) S1($/€) debt portfolio C1($/€) $1.875 – $1.20 = $.675 $.375 $1.50 7-47 $1.20 – $1.20 = $0 $0 Binomial Option Pricing Model The replicating portfolio’s dollar value today is the sum of today’s dollar value of the present value of one euro less the present value of a $1.20 debt: €1.00 × $1.50 – $1.20 (1 + i€) €1.00 (1 + i$) S0($/€) S1($/€) debt portfolio C1($/€) $1.875 – $1.20 = $.675 $.375 $1.50 7-48 $1.20 – $1.20 = $0 $0 Binomial Option Pricing Model We can value the call option as 5/9 of the value of the replicating portfolio: 5 €1.00 × $1.50 – $1.20 × C0 = 9 (1 + i€) €1.00 (1 + i$) S0($/€) $1.50 7-49 S1($/€) debt portfolio C1($/€) $1.875– $1.20 = $.675 $.375 If i$ = 3% and i€ = 2% the call is worth 5 $1.20 €1.00 $1.50 $0.1697 = × – × 9 (1.02) €1.00 (1.03) $1.20 – $1.20 = $0 $0 Binomial Option Pricing Model The most important lesson from the binomial option pricing model is: the replicating portfolio intuition. Many derivative securities can be valued by valuing portfolios of primitive securities when those portfolios have the same payoffs as the derivative securities. 7-50 The Hedge Ratio In the example just previous, we replicated the payoffs of the call option with a levered position in the underlying asset. (In this case, borrowing dollars to buy euro at the spot.) The hedge ratio of a option is the ratio of change in the price of the option to the change in the price of the underlying asset: C up– C down H = up S1 – S1down This ratio gives the number of units of the underlying asset we should hold for each call option we sell in order to create a riskless hedge. 7-51 Hedge Ratio This practice of the construction of a riskless hedge is called delta hedging. The delta of a call option is positive. Recall from the example: $0.375 5 $0.375 – $0 C up– C down = = H = up down = 9 S1 – S1 $1.875 – $1.20 $0.675 The delta of a put option is negative. Deltas change through time. 7-52 Creating a Riskless Hedge The standard size of euro options on the PHLX is €10,000. In our simple world where the dollar-euro exchange rate is S0($/€) = $1.50/€ today and in the next year, S1($/€) is either $1.875/€ or $1.20/€ an at-the-money call on €10,000 has these payoffs: If the exchange rate at maturity goes up to S1($/€) = $1.875/€ then the option finishes in-the-money. $1.875 × €10,000 = $18,750 €1.00 – $15,000 C1up = $3,750 $1.50 × €10,000 = $15,000 €1.00 If the rate goes down, the option finishes out of the money. No one will pay $15,000 for €10,000 worth $12,000 7-53 $1.20 × €10,000 = $12,000 €1.00 C1down = $0 Creating a Riskless Hedge Consider a dealer who has just written 1 at-the-money call on €10,000. He calculates the hedge ratio as 5/9: $3,750 5 C up– C down = $3,750 – 0 = = H = up down $18,750 – $12,000 $6,750 9 S1 – S1 He can hedge his position with three trades: 1. If i$ = 3% then he could borrow $6,472.49 today and owe $6,666.66 in one period. 5 $12,000 × = $6,666.66 9 2. $6,666.66 $6,472.49 = 1.03 Then buy the present value of €5,555.56 = €10,000 × 5 9 (buy euro at spot exchange rate, €5,555.56 compute PV at i€ = 2%), €5,446.62 = 1.02 3. Invest €5,446.62 at i€ = 2%. 7-54 Net cost of hedge = $1,697.44 Service Loan FV € investment in $ T=0 FV € investment S1($|€) Replicating Portfolio Call on €10,000 K($/€) = $1.50/€ T=1 Step 1 Borrow $6,472.49 at i$ = 3% $1.875 ×€5,555.56 = $10,416 – $6,666 = $3,750 €1.00 Step 2 the replicating portfolio payoffs and the call Buy €5,446.62 at option payoffs are the same so the call is worth S0($|€) = $1.50/€ €10,000 = $15,000 5 × €10,000 $1.20 $1.50 $1,697.44 = – × 9 (1.02) €1.00 (1.03) Step 3 Invest €5,446.62 at i€ = 2% Net cost = $1,697.44 7-55 $1.20 × €5,555.56 = $6,666.67 – $ 6,666.67 = 0 €1.00 Risk Neutral Valuation of Options Calculating the hedge ratio is vitally important if you are going to use options. 7-56 The seller needs to know it if he wants to protect his profits or eliminate his downside risk. The buyer needs to use the hedge ratio to inform his decision on how many options to buy. Knowing what the hedge ratio is isn’t especially important if you are trying to value options. Risk Neutral Valuation is a very hand shortcut to valuation. Risk Neutral Valuation of Options We can safely assume that IRP holds: $1.5147 $1.50×(1.03) = F1($/€) = €1.00×(1.02) €1.00 $1.875 × €10,000 $18,750 = €1.00 €10,000 = $15,000 $12,000 = $1.20 × €10,000 €1.00 Set the value of €10,000 bought forward at $1.5147/€ equal to the expected value of the two possibilities shown above: $1.5147 €10,000× €1.00 = $15,147.06 = p × $18,750 + (1 – p) × $12,000 7-57 Risk Neutral Valuation of Options Solving for p gives the risk-neutral probability of an “up” move in the exchange rate: $15,147.06 = p × $18,750 + (1 – p) × $12,000 $15,147.06 – $12,000 p= $18,750 – $12,000 p = .4662 7-58 Risk Neutral Valuation of Options Now we can value the call option as the present value (discounted at the USD risk-free rate) of the expected value of the option payoffs, calculated using the riskneutral probabilities. $1.875 × €10,000 ←value of €10,000 €1.00 $3,750 = payoff of right to buy €10,000 for $15,000 $18,750 = €10,000 = $15,000 $1,697.44 $1.20 × €10,000 ←value of €10,000 $12,000 = €1.00 $0 = payoff of right to buy €10,000 for $15,000 .4662×$3,750 + (1–.4662)×0 C0 = $1,697.44 = 7-59 1.03 Currency Futures Options Are an option on a currency futures contract. Exercise of a currency futures option results in a long futures position for the holder of a call or the writer of a put. Exercise of a currency futures option results in a short futures position for the seller of a call or the buyer of a put. If the futures position is not offset prior to its expiration, foreign currency will change hands. 7-60 Currency Futures Options Why a derivative on a derivative? Transactions costs and liquidity. For some assets, the futures contract can have lower transactions costs and greater liquidity than the underlying asset. Tax consequences matter as well, and for some users an option contract on a future is more tax efficient. The proof is in the fact that they exist. 7-61 Exercises EOC Problems 8-12 End Chapter Seven 7-63