FRM Part I · FRM Exam Part I
Options Markets: formula sheet
Key formulas
- Long call payoff
- max(S_T − K, 0)
- S_T is the underlying price at expiration. Never negative.
- Long put payoff
- max(K − S_T, 0)
- Never negative.
- Short call payoff
- −max(S_T − K, 0) = min(K − S_T, 0)
- Mirror image of the long call.
- Short put payoff
- −max(K − S_T, 0) = min(S_T − K, 0)
- Mirror image of the long put.
- Profit for the buyer
- Profit = Payoff − Premium
- Ignores interest on the premium unless stated.
- Profit for the seller
- Profit = Premium − Buyer's payoff
- Maximum gain is the premium.
- Breakeven price
- Call: K + premium. Put: K − premium
- For the long position. Short has the same breakeven.
- Maximum gain on a long put
- K − premium
- Occurs when S_T = 0.
- Split adjustment (n-for-m)
- New strike = Old strike × m ÷ n; New contracts' shares = Old shares × n ÷ m
- In an n-for-m split, you get n new shares for m old. A 3-for-2 split multiplies the strike by 2/3 and shares by 3/2.
- Stock dividend as split
- x% stock dividend = (100 + x)-for-100 split
- A 25% stock dividend is 5-for-4, so strike × 4/5 and shares × 5/4.
- Cash dividend adjustment
- No adjustment to strike or size for exchange-traded options
- Exceptions exist only for very large special dividends, so a standard question assumes none.
- Naked equity call margin (US-style, as in Hull)
- Margin = greater of (1) 100% of option proceeds + 20% of underlying value − out-of-the-money amount, and (2) 100% of option proceeds + 10% of underlying value
- Per share, then multiply by contract size. Out-of-the-money amount for a call = max(K − S, 0). Use the percentages given in the question.
- Naked put margin (US-style, as in Hull)
- Margin = greater of (1) 100% of proceeds + 20% of underlying value − out-of-the-money amount, and (2) 100% of proceeds + 10% of exercise price
- Out-of-the-money amount for a put = max(S − K, 0).
- Contract value
- Premium paid = quoted premium × shares per contract × number of contracts
- Quotes are per share.
- Effect summary (increase in the factor)
- S0 ↑: call ↑, put ↓ | K ↑: call ↓, put ↑ | σ ↑: call ↑, put ↑ | r ↑: call ↑, put ↓ | dividends ↑: call ↓, put ↑
- Holds for all other factors fixed. Time to expiry is ↑ for American options; ambiguous for some European ones.
- Upper bound, call
- c ≤ S0 and C ≤ S0
- A call cannot be worth more than the stock.
- Upper bound, put
- American: P ≤ K | European: p ≤ K e^(−rT)
- The most a put can pay is K, or K discounted for a European put.
- Lower bound, European call (no dividends)
- c ≥ max(S0 − K e^(−rT), 0)
- Also the lower bound for an American call on a non-dividend stock.
- Lower bound, European put (no dividends)
- p ≥ max(K e^(−rT) − S0, 0)
- American put: P ≥ max(K − S0, 0).
- Lower bounds with known dividends
- c ≥ max(S0 − D − K e^(−rT), 0) | p ≥ max(K e^(−rT) + D − S0, 0)
- D is the present value of dividends during the option's life.
- American versus European
- C ≥ c and P ≥ p
- The early exercise right can only add value.
- Put-call parity (no dividends, European)
- c + K·e^(−rT) = p + S0
- Same strike, same expiry, same underlying. r is the continuously compounded risk-free rate.
- Parity with discrete dividends
- c + D + K·e^(−rT) = p + S0
- D is the present value of dividends paid during the option's life.
- Parity with continuous dividend yield
- c + K·e^(−rT) = p + S0·e^(−qT)
- q is the continuous dividend yield.
- American options, no dividends
- S0 − K ≤ C − P ≤ S0 − K·e^(−rT)
- An inequality only. C and P are American prices.
- American options, with dividends
- S0 − D − K ≤ C − P ≤ S0 − K·e^(−rT)
- D is the present value of dividends. This form is stated for discrete dividends.
- Discrete compounding version
- c + K ÷ (1 + r)^T = p + S0
- Use when the question gives an annual effective rate.
- Bull call spread payoff
- Payoff = max(S − K1, 0) − max(S − K2, 0), K1 < K2
- Long K1 call, short K2 call. Maximum payoff is K2 − K1. Profit = payoff − net premium.
- Bull call spread: max profit and max loss
- Max profit = (K2 − K1) − net debit; Max loss = net debit
- Breakeven = K1 + net debit.
- Bull put spread
- Max profit = net credit; Max loss = (K2 − K1) − net credit
- Long K1 put, short K2 put. Breakeven = K2 − net credit.
- Bear put spread payoff
- Payoff = max(K2 − S, 0) − max(K1 − S, 0), K1 < K2
- Long K2 put, short K1 put. Maximum payoff is K2 − K1. Breakeven = K2 − net debit.
- Butterfly spread with calls
- Payoff = max(S − K1, 0) − 2 max(S − K2, 0) + max(S − K3, 0)
- Maximum payoff is K2 − K1 at S = K2. With evenly spaced strikes (K2 − K1 = K3 − K2), the minimum payoff is 0. With unequal spacing, the payoff for S ≥ K3 is 2K2 − K1 − K3, which is negative if K3 − K2 > K2 − K1.
- Butterfly breakevens
- Lower = K1 + net debit; Upper = K3 − net debit
- Max profit = (K2 − K1) − net debit. Max loss = net debit.
- Long straddle profit (strike K)
- Profit = max(S_T − K, 0) + max(K − S_T, 0) − (c + p) = |S_T − K| − (c + p)
- Break-evens: K + (c + p) and K − (c + p). Maximum loss is c + p at S_T = K. Gain is unlimited on the upside.
- Long strangle profit (put strike K1 < call strike K2)
- Profit = max(S_T − K2, 0) + max(K1 − S_T, 0) − (c + p)
- Break-evens: K2 + (c + p) and K1 − (c + p). Maximum loss is c + p for any S_T between K1 and K2.
- Strip (1 call + 2 puts, strike K)
- Profit = max(S_T − K, 0) + 2 × max(K − S_T, 0) − (c + 2p)
- Bearish tilt. Break-evens: K + (c + 2p) above, and K − (c + 2p) ÷ 2 below.
- Strap (2 calls + 1 put, strike K)
- Profit = 2 × max(S_T − K, 0) + max(K − S_T, 0) − (2c + p)
- Bullish tilt. Break-evens: K + (2c + p) ÷ 2 above, and K − (2c + p) below.
- Covered call profit
- Profit = (S_T − S_0) − max(S_T − K, 0) + c
- Maximum profit = K − S_0 + c, reached when S_T ≥ K. Loss is large if the stock falls.
- Protective put profit
- Profit = (S_T − S_0) + max(K − S_T, 0) − p
- Maximum loss = S_0 − K + p, when S_T ≤ K. Upside is unlimited.
- Put-call parity link (European, no dividends)
- S_0 + p = c + K × e^(−rT)
- Shows a protective put is equivalent to a long call plus cash. A covered call is equivalent to a short put plus cash.
- Vanilla call and put payoff
- Call = max(S_T − K, 0); Put = max(K − S_T, 0)
- The base case to compare every exotic against.
- Cash-or-nothing binary call payoff
- Q if S_T > K; 0 otherwise
- Q is the fixed cash amount. The put pays Q if S_T < K.
- Asset-or-nothing binary call payoff
- S_T if S_T > K; 0 otherwise
- A vanilla call equals an asset-or-nothing call minus K cash-or-nothing calls.
- Average-price Asian call payoff
- max(S_avg − K, 0)
- S_avg is the average price over the averaging period. Average-strike call: max(S_T − S_avg, 0).
- Floating lookback payoffs
- Call = S_T − S_min; Put = S_max − S_T
- Always zero or positive. S_min and S_max are observed over the option's life.
- Barrier in-out parity
- Knock-in + Knock-out = Vanilla (same K, T, barrier)
- Holds when there is no rebate. Lets you price one from the other.
Quick revision
- Long call payoff = max(S_T − K, 0); long put payoff = max(K − S_T, 0).
- Profit = payoff − premium paid for a long position; the short position is the mirror image.
- A call gains from a higher underlying price; a put gains from a lower one.
- Higher volatility raises the value of both calls and puts.
- Higher interest rates raise call values and lower put values, other things equal.
- Expected dividends lower call values and raise put values.
- Put-call parity (European, no dividends): c + K·e^(−rT) = p + S₀.
- With a known present value of dividends D: c + D + K·e^(−rT) = p + S₀.
- Bull spread: long a lower strike, short a higher strike; bear spread is the reverse.
- Straddle: long a call and a put at the same strike; it gains from a large move either way.
- Covered call: long the stock and short a call; protective put: long the stock and long a put.
- Barrier options are path dependent; Asian options depend on an average price.
Common mistakes
- Forgetting the premium when asked for profit. Fix: Read whether the question says payoff or profit. For profit, always subtract the premium if long.
- Confusing a short put with a long call. Fix: A long call has a capped loss and unlimited gain. A short put has a capped gain (premium) and a large loss if the price falls.
- Adjusting the strike for ordinary cash dividends on exchange-traded options. Fix: Exchange-traded options are protected against splits and stock dividends only. Cash dividends are handled by the market price of the option.
- Multiplying the strike by n/m instead of m/n in a split. Fix: Check that the strike falls after a split. A 2-for-1 split halves the strike. Verify strike × shares is unchanged.
- Saying higher volatility lowers the value of a put. Fix: The holder's loss is capped at the premium while the gain is not. Higher volatility raises both calls and puts.
- Using K instead of K e^(−rT) in the lower bound of a European option. Fix: Discount the strike from expiry to today. Write S0 − K e^(−rT) every time.
- Using S0 instead of the discounted strike, or forgetting to discount K Fix: Parity is stated today. The strike is paid at T, so discount it: K·e^(−rT).
- Applying the equality to American options Fix: Check the option style. For American options only the bound S0 − K ≤ C − P ≤ S0 − K·e^(−rT) holds.
- Calling a bull put spread a bearish trade because you sell a put Fix: Bull means long the lower strike and short the higher strike. The bull put spread has the same payoff shape as the bull call spread but is a credit trade.
- Forgetting the net premium when finding profit Fix: Always compute net premium first. Profit = payoff + net credit, or payoff − net debit.
Exam tips
- Read whether the question asks for payoff or profit, and whether you are long or short. These two reads decide the answer.
- Use the kink at K and the premium level to match a diagram to a position quickly.
- Remember the put's maximum gain is K minus the premium, because the price cannot go below zero.
- Check moneyness against S and K only. Distractor answers often mix in the premium.
- Premium is usually not discounted in these questions. Only adjust for interest if the question states it.
- Expect numeric split adjustments. Practice n-for-m and stock dividend conversions until the strike × shares check is automatic.
- Know which events adjust the contract: splits and stock dividends yes, ordinary cash dividends no.
- Questions on the clearing house test the idea that it is the counterparty to both sides and removes bilateral credit risk. Only OTC trades carry it, unless centrally cleared.