Weekly Option Trader

Introducing: Delta

Options are complex!  Their value being determined by a long mathematical equation, with many sub-equations and variables.  I can’t write the formulas out for you.  Not because they’re secret, but because my keypad doesn’t contain the crazy looking symbols used in the formulas.

Each aspect of option pricing is a separate component of the formula. To remove confusion, each component has a Greek title; Delta, Gamma, Theta, Vega, and Rho.  Do you wonder? Should that last sentence read, “To ADD confusion?”  Everyone knows Vega is not Greek.  It’s a Chevrolet.

The first and most important of the “Greeks” is Delta.  It is probably one of the most common known of the “Greeks,” but it can be looked at three ways.  Two of which are widely accepted.  The third is far less important and really only theoretical.  Most quasi-knowledgeable traders only know one or two.

The first and most important way to look at Delta:  Delta measures the rate of change in an option’s price compared to a one point ($1) movement in the underlying security.

Since the rate of change in the price of a stock is measured dollar for dollar, their movement is 100%.  Stocks have a Delta of 1.00.  Don’t worry; stock prices do not have any other “Greeks,” only Delta.

Option prices, which don’t move the same dollar for dollar as stock prices, have lower Deltas.  Think of it as a percentage of the movement of the stock price.  If a stock goes up $1 and an option on that stock went up 1/2, it had a Delta of .50.

Many times Deltas are not mentioned with decimals but as whole numbers.  Since options trade 100 shares of stock per contract, the decimals are dropped.  Example:  .50 x 100 = 50.

Deltas can never be over 1.00 (one hundred).  If you ever see an option move greater than the underlying, it was caused by another of the “Greeks.”  In our examples, we will assume everything else remains constant.  In reality, the other “Greek” forces are at work, but for explanation sake, they will remain silent.

The at the money (ATM) Call will typically have a delta of .50.  In the money (ITM) will have a higher delta.  The Delta is still higher on deep in the money (DITM).  The opposite is true for out of the money (OTM) and deep out of the money (DOTM) options, their Deltas are lower.

An understanding of Delta helps option traders choose strike prices.  To be profitable with small price movements, you will need to buy ATM or maybe even ITM options.  The difference between the Bid/Ask spread may be too great to overcome with OTM options.

The parameters of our hypothetical example:  $30 stock, $25 Call price $6 Delta .75, $30 Call price $2 Delta .50, $35 Call price $1 Delta .25.  If the stock price increases $1 to $31, the $25 Call would increase .75 to $6.75.  The $30 Call would rise to $2.50, the $35 Call would increase to $1.25.

Let’s say the Bid/Ask spread on the $35 Call was .75/1.00 when the stock was $30.  After the $1 price rise in the stock the Bid/Ask spread might have become 1.00/1.25.  If you buy @ $1 and can only sell @ $1, you lose the cost of commissions.

Delta is dynamic.  When the stock price moves, the Delta changes.  Delta will increase as the stock price increases.  Delta will decrease if the stock price falls.  This change is known as Gamma.  Think of Delta as speed and Gamma as acceleration.  We will go into Gamma later in much greater detail.

Delta also changes as time passes.  As option expiration gets closer the Delta for the ITM option increases towards 1.00, and the Delta for the OTM option decreases towards .00, while the ATM option’s Delta will almost hold at .50, right until expiration.

OTM options are usually a bad deal.  There’s generally not enough time for the price to rise and the Delta is too low, the exception is with Leaps.  The Deltas on Leaps will be closer to .50.  ITM Leaps will have lower Deltas than short term options.  OTM Leaps will have higher Deltas than short term options.  Most people are unaware of this phenomenon.  It can be used to great advantage in calendar spreads.

Every option trader should know Delta!  Its okay not to know Rho, but knowledge of Delta is essential.  You will need to understand Delta before trying to grasp Gamma (my favorite).

In order to understand option strategies, especially using weekly options it is necessary to understand Delta – hopefully you do now.  As always if you have any comments please leave them below.