There is always potential for the market or individual stocks to move lower. In fact many option traders never even think about bearish strategies. Option traders know that stocks and markets do not always go up, but many will wait until they think the decline is over to once again look for a bullish strategy instead of taking advantage of bearish opportunity at hand. Understanding put options is a must for option traders but I am often asked how to choose strike prices. There are several different options to consider and here are a few things to consider specifically based on an expected small move in the underlying. But first let us take break down the anatomy of a put option.
A buyer of a put option has the right, but not the obligation to sell shares of underlying stock at a certain price on or before an expiration day. The price at which the buyer can sell the shares is called the strike price. There are many strike prices and expirations to choose from which can be overwhelming for a trader. When expecting a stock to make a small move especially if the stock is lower in price, it may be advantageous for the trader to select an in-the-money (ITM) put option. An ITM put option is a put with a strike price that is higher than the stock’s current price. Before going further, here’s a look at a possible scenario where buying an ITM put might be warranted.
An ITM put option can be used to capture a relatively small move lower. Suppose an option trader is watching a $10 stock in a downtrend. The stock then rallies higher and now he thinks it is a good time to enter a bearish position with a put option. He surmises the stock might be able to drop about $0.50.
A critical point about capturing this potential $0.50 move down revolves around option delta. Option delta is the rate of change in the option’s value relative to the change in the stock price. Puts have a negative option delta because if the stock rises, puts will lose some of their value. Since puts give the owner the right to sell stock, puts gain value as the stock falls. In this example, the trader is expecting only a $0.50 move lower. Buying an ITM put that has a higher option delta will profit more than a put with a smaller option delta if the anticipated move comes to fruition.
With the stock trading just under $10, the option trader looks at the 10 and 12 strike puts. The 10 strike puts have an option delta of about -0.55 and the 12 strike puts have an option delta of about -0.90. This means that for every $1.00 the stock moves down, the 10 strike put’s premium should increase by $0.55 and the 12 strike put’s premium should increase by $0.90 all other factors held constant. The reverse is also true. If the stock moves higher by $1.00, each put would lose value in the amount of their deltas. Since the expected move is only $0.50, half the deltas would be gained or loss depending on the direction of the stock.
Buying an ITM put option is not always the best way to capture a stock’s move lower, but when it comes to profiting on a perceived small move, an option trader should consider a put option with a higher option delta and do so with the satisfaction of knowing their loss potential is limited to the cost of the put option.
Senior Options Instructor