Chapter 5 Options
Options
An Option is a contract that gives the right, but not the obligation, to buy or sell the underlying asset on or before a stated date, at a stated price. The party taking a long position, i.e. buying the option is called buyer/holder of the Option and the party taking a Short position, i.e. selling the Option is called the seller/writer of the Option; the contract value and lots size are similar to Futures.
Types of Options
There are two types of Options:
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Call Option
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Put Option
Options, which give you a right to buy the underlying asset, are called Call Options. On the other hand, the Options that give you a right to sell the underlying asset are called Put Options.
Key features
Index Option
These Options have Index as the underlying asset. For example, options on Nifty, Sensex, Bank Nifty etc.
Stock Option
These Options have individual stocks as the underlying asset. Examples include Options on ONGC, NTPC, etc.
Buyer of an Option
The buyer of an Option has a right but not the obligation in the contract. For owning this right, you pay a price to the seller of this right, called ‘option premium’.
Writer of an Option
The writer of an Option receives the Option premium and is thereby obliged to sell the asset if the buyer of Option exercises his right.
Option Price/Premium
It is the price which you, as an Option buyer, pay to the Option seller.
Lot Size
Lot size is the number of units of underlying asset in a contract.
Expiration Day
This is the day on which a derivative contract ceases to exist. It is the last trading date of the contract. The expiration day of Nifty contracts is Aug 31, 2017 in the following example.
Spot Price
It is the price at which the underlying asset trades in the spot market. Underlying stock value of Nifty option was 9912 as on Aug 28, 2017.
Strike Price or Exercise Price
Strike price is the price per share for which the underlying security may be purchased or sold by the Option holder. For e.g. when underlying value of NIFTY is 9912, then prices of 9900 Call and 9900 Put is:
| Underlying | Expiry Date | Option Type | Strike Price | Option Premium |
| NIFTY | 31 Aug 2017 | Call | 9900 | 50.10 |
| NIFTY | 31 Aug 2017 | Put | 9900 | 33.15 |
Open Interest
As discussed in futures section, Open Interest is the total number of Option contracts outstanding for an underlying asset.
Option Premium
Intrinsic Value
Option premium, consists of two components - intrinsic value and time value.
For an Option, intrinsic value refers to the amount by which an Option is in the money, i.e. the amount an Option buyer will realize, before adjusting for premium paid, if he exercises the Option instantly.
Therefore, only in-the-money Options have intrinsic value whereas at-the-money and out-of-the-money Options have zero intrinsic value. The intrinsic value of an Option can never be negative. Thus, for call Option, which is in-the-money, intrinsic value is the excess of spot price (S) over the exercise price (X).
Intrinsic value of a Call Option can be calculated as S-X, with a possible minimum value of zero because no one would like to exercise his right under no advantage condition. Similarly, for Put Option which is in-the-money, intrinsic value is the excess of exercise price (X) over the spot price (S). Thus, intrinsic value of Put Option can be calculated as X-S, with minimum possible value of zero.
Time Value
It is the difference between premium and intrinsic value, if any, of an Option. ATM and OTM Options will have only time value because the intrinsic value of such Options is zero.
Option Greeks
Delta
Delta measures the change in Option price for a unit change in the price of underlying. So if my delta is 0.46, it shows that for each unit increase/decrease in underlying, Option price will increase/decrease by 0.46.
Important points for Delta:
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Delta of Call Option is always positive and Delta of Put Option is always negative.
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When you buy Call Option, Delta is positive and when you sell Call Option, Delta is negative.
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When you buy Put Option, Delta is negative and when you sell Put Option, Delta is positive.
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Call Delta ranges from 0 to 1 and Put Delta ranges from 0 to -1
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Total of absolute value of call Delta and put Delta always comes to 1
Gamma
Gamma measures the change in Delta with respect to per unit change in underlying. If Gamma value is 0.0008, it shows that the next move in Delta will be 0.0008 if underlying changes by 1. So Gamma shows what will be the next change in Delta with respect of change in underlying.
Important points for Gamma:
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Gamma of Option is always positive.
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Gamma of Call and Put Option is same.
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Gamma is highest at ATM & decreases as Underlying moves away.
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Call Delta ranges from 0 to 1 and Put Delta ranges from 0 to -1
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Gamma of Future is 0.
Vega
Vega measures the change in Options price per unit change in volatility. A Vega value of 6.87 shows that for every unit increase in volatility, Option price will increase by 6.87. Thus, Vega shows effect of volatility on Option price.
Theta
Theta measures the change in Option price per day change in time to expiry. If Theta is -3.87, it signifies that for each day passing towards expiry, the Options price will decrease by 3.87.
Rho
Rho measures the change in Option price per unit change in interest rate. A Rho value of 2 shows that for every unit increase in interest rate, Option price will change by 2. Rho is inversely related to puts and directly related to calls.
In the Money (ITM) option
A Call Option is said to be ITM when spot price is higher than strike price. A Put Option is said to be ITM when spot price is lower than strike price.
For example, last traded price of different ITM Calls and Puts, when underlying Nifty is trading at 9912, are as follows:
| Strike Price | LTP of Calls |
| 9900 | 51.8 |
| 9850 | 85.3 |
| 9800 | 128.9 |
| 9750 | 171.4 |
| 9700 | 217.75 |
| 9650 | 262.05 |
| Strike Price | LTP of Puts |
| 9950 | 57.35 |
| 10000 | 92.55 |
| 10050 | 133.95 |
| 10100 | 179.75 |
| 10150 | 235.1 |
| 10200 | 279.35 |
At the Money (ATM) Option
At-The-Money is a situation where an Option’s strike price is same as the price of the underlying security. Both the Call and Put Options are simultaneously At-The-Money. At-The-Money Options have no intrinsic value, but it may still have time value.
Out of the Money (OTM) Option
Call Option is said to be OTM, when spot price is lower than strike price. And a Put Option is said to be OTM when spot price is higher than strike price.
For example, last traded price of different OTM Calls and Puts, when underlying Nifty is trading at 9912, are as follows:
| Strike Price | LTP of Calls |
| 9950 | 28.65 |
| 10000 | 14.3 |
| 10050 | 6.45 |
| 10100 | 3.15 |
| 10150 | 1.6 |
| 10200 | 1 |
| Strike Price | LTP of Puts |
| 9900 | 34.35 |
| 9850 | 20.25 |
| 9800 | 12.9 |
| 9750 | 7.9 |
| 9700 | 5.25 |
| 9650 | 3.05 |
Difference between ITM, ATM and OTM
Exercise of Options
In case of American option, buyers can exercise their Option any time before the maturity of contract. All these Options are exercised with respect to the settlement value/closing price of the stock on the day of exercise of Option.
Payoff Diagram
Long Call Payoff
On Aug 28, 2017, Nifty was trading at 9912. Assume that you buy a Call Option with strike price of 9900 at a premium of Rs. 52 with expiry date Aug 31, 2017.
Scenario Analysis at various expiry levels:
| Spot Closing at Expiry | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Instrument | Action | Strike | Premium | No of Lots | 9600 | 9700 | 9800 | 9900 | 10000 | 10100 | 10200 |
| Call | Buy | 9900 | 52 | 1 | -52 | -52 | -52 | -52 | 48 | 148 | 248 |
Long Put Payoff
On Aug 28, 2017, Nifty is at 9912. Assume that you buy a Put Option with strike price of 9900 at a premium of Rs.34 with expiry date Aug 31, 2017.
Scenario Analysis at various expiry levels:
| Spot Closing at Expiry | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Instrument | Action | Premium | Strike | No of Lots | 9600 | 9700 | 9800 | 9900 | 10000 | 10100 | 10200 |
| Put | Buy | 9900 | 34 | 1 | 266 | 166 | 66 | -34 | -34 | -34 | -34 |
Opening a Position
An opening transaction is one that adds or creates a new trading position. It can be either a purchase or a sale. With respect to an Option transaction, we will consider both:
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Opening purchase – This is done with the purchasing intention of creating or increasing a long position in a given series of Options.
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Opening sale – This is done with the selling intention of creating or increasing a Short position in a given series of Options.
Closing a Position
A Closing transaction is one that reduces or eliminates an existing position by an appropriate offsetting purchase or sale. This is also known as “squaring off” your position. With respect to an Option transaction:
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Closing purchase – This is done with the purchasing intention of reducing or eliminating a short position in a given series of Options. This transaction is frequently referred to as “covering” a short position.
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Closing sale – This is done with the selling intention of reducing or eliminating a long position in a given series of Options.
You cannot close out a long call position by purchasing a Put or any other similar transaction. A closing transaction for an Option involves the sale of an Option contract with the same terms.
Leverage
You, as an Option buyer, pay a relatively small premium for market exposure in relation to the contract value. This is known as Leverage. You can see large percentage gains from comparatively small, favorable percentage moves in the underlying equity. Leverage also has downside implications. If the underlying price does not rise/falls during the lifetime of the Option, Leverage can magnify your percentage loss.
| Risk | Return | |
|---|---|---|
| Long | Premium paid | Unlimited |
| Short | Unlimited | Premium received |
A Long Option position has limited risk (premium paid) and unlimited profit potential. A Short Option position has unlimited downside risk, but limited upside potential (to the extent of premium received).
Option Trading Strategies
Bullish Strategies
Bearish Strategies
Neutral Strategy
Long Call Calendar Spread Strategy
Volatility Strategies
Key Takeaways
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There are two types of Options - Call Option and Put Option.
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Call Option is bought when view is bullish.
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Put Option is bought when view is bearish.
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Buyer of Option pays the Option premium.
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Writer of the Option receives the Option premium.
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Only ITM Options have intrinsic value.
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Time value is the difference between premium and intrinsic value.
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Delta measures the change in Option price for a unit change in the price of underlying.
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Gamma measures the change in Delta with respect to per unit change in underlying.
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Vega measures the change in Options price per unit change in volatility.
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Theta measures the change in Option price per day change in time to expiry.
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Rho measures the change in Option price per unit change in interest rate.
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All option strategies use basic Call and Put Options.