Specifically, delta is the rate at which the price of an option contract will move compared to the price of its underlying market. Delta is one of the most commonly used options Greeks. A call option will have a delta value between 0 and 1, while a put option will have a delta value between 0 and For example, if a call option has a delta of 0.
The buyer of a put option makes money if the underlying asset goes down, which is why put delta values are negative, but the concept is same. Typically delta can be thought of as a percentage, as opposed to a momentary number. For example, a delta of 0. Since options prices both puts and calls can be affected by both up and down price movements in the underlying asset, it is beneficial to know the delta for both up and down movements in the underlying asset.
In other words, the option price is more sensitive to price increases than it is to price declines. The opposite could also be true. A number of factors can cause this, including how far in or out of the money an option is, volatility and time until expiration. Time will affect delta, because time brings the option closer to expiry.
As an option nears expiration, options that are near the money or in the money will see their delta values increase, because close to expiration that option should move very similarly to the underlying asset see What are In the Money and Out of the Money Options.
For options that are out of the money, and not close to being in the money, the delta value will decrease toward 0. With almost no time till expiration, if the option isn't close to being in the money, there is little reason for traders to buy it, and therefore the movements in the price of the underlying asset will have less and less affect on the option price unless it gets to close being in the money.
Volatility also affects delta. Volatility increases the chances of an option moving into the money, therefore out of the money options tend to see an increase in delta as volatility increases. In the money options have a tendency to see their delta value decrease as volatility moves up.
Delta can be used as a way to estimate profits on options positions, based on how much the underlying asset moves. Delta is also used in hedging, and can show how many options contracts are needed to attain or hedge a position in the underlying. For example, if a stock options contract gives the right to one hundred shares has a delta of 0. Delta is therefore often used to determine the number of options contracts that must be traded in order to replicate a specific number of shares. If a trader wants to trade five hundred shares of XYZ using an option with a delta of 0.
This is calculated as:. Keep in mind though, delta does change over time. Maintaining an option position that approximates shares may involve buying more or selling some of your options contracts over time. Delta is useful for seeing how the option price moves relative to the underlying asset price. This can help establish how much your option may be worth based on how much the underlying asset moves.
Updated February 15, What Delta Values Mean in Options Trading A call option will have a delta value between 0 and 1, while a put option will have a delta value between 0 and Final Word On Options Greek Delta Delta is useful for seeing how the option price moves relative to the underlying asset price.More...