CHAPTER 4
Option-Specific Risk and Opportunity
New endeavors can be intimidating. The first day at a new job or new school is a challenge. Option trading is no different. When traders first venture into the world of options, they tend to start with what they know—trading direction. Buying stocks is at the heart of the comfort zone for many traders. Buying a call as a substitute for buying a stock is a logical progression. And for the most part, call buying is a pretty straightforward way to take a bullish position in a stock. But it’s not
just
a bullish position. The greeks come into play with the long call, providing both risk and opportunity.
Long ATM Call
Kim is a trader who is bullish on the Walt Disney Company (DIS) over the short term. The time horizon of her forecast is three weeks. Instead of buying 100 shares of Disney at $35.10 per share, Kim decides to buy one Disney March 35 call at $1.10. In this example, March options have 44 days until expiration. How can Kim profit from this position? How can she lose?
Exhibit 4.1
shows the profit and loss (P&(L)) for the call at different time periods. The top line is when the trade is executed; the middle, dotted line is after three weeks have passed; and the bottom, darker line is at expiration. Kim wants Disney to rise in price, which is evident by looking at the graph for any of the three time horizons. She would anticipate a loss if the stock price declines. These expectations are related to the position’s delta, but that is not the only risk exposure Kim has. As indicated by the three different lines in
Exhibit 4.1
, the call loses value over time. This is called
theta risk
. She has other risk exposure as well.
Exhibit 4.2
lists the greeks for the DIS March 35 call.
EXHIBIT 4.1
P&(L) of Disney 35 call.
EXHIBIT 4.2
Greeks for 35 Disney call.
Delta
0.57
Gamma
0.166
Theta
−0.013
Vega
0.048
Rho
0.023
Kim’s immediate directional exposure is quantified by the delta, which is 0.57. Delta is immediate directional exposure because it’s subject to change by the amount of the gamma. The positive gamma of this position helps Kim by increasing the delta as Disney rises and decreasing it as it falls. Kim, however, has time working against her—theta. At this point, she theoretically loses $0.013 per day. Since her call is close to being at-the-money, she would anticipate her theta becoming more negative as expiration approaches if Disney’s share price remains unchanged. She also has positive vega exposure. A one-percentage-point increase in implied volatility (IV) earns Kim just under $0.05. A one-point decrease costs her about $0.05. With so few days until expiration, the 35-strike call has very little rho exposure. A full one-percentage-point change in the interest rate changes her call’s value by only $0.023.
Delta
Some of Kim’s risks warrant more concern than others. With this position, delta is of the greatest concern, followed by theta. Kim expects the call to rise in value and accepts the risk of decline. Delta exposure was her main rationale for establishing the position. She expects to hold it for about three weeks. Kim is willing to accept the trade-off of delta exposure for theta, which will cost her three weeks of erosion of option premium. If the anticipated delta move happens sooner than expected, Kim will have less decay.
Exhibit 4.3
shows the value of her 35 call at various stock prices over time. The left column is the price of Disney. The top row is the number of days until expiration.
EXHIBIT 4.3
Disney 35 call price–time matrix–value.
The effect of delta is evident as the stock rises or falls. When the position is established (44 days until expiration), the change in the option price if the stock were to move from $35 to $36 is 0.62 (1.66 − 1.04). Between stock prices of $36 and $37, the option gains 0.78 (2.44 −1.66). If the stock were to decline in value from $35 to $34, the option loses 0.47 (1.04 − 0.57). The option gains value at a faster rate as the stock rises and loses value at a slower rate as the stock falls. This is the effect of gamma.
Gamma
With this type of position, gamma is an important but secondary consideration. Gamma is most helpful to Kim in developing expectations of what the delta will be as the stock price rises or falls.
Exhibit 4.4
shows the delta at various stock prices over time.
EXHIBIT 4.4
Disney call price–time matrix–delta.
Kim pays attention to gamma only to gauge her delta. Why is this important to her? In this trade, Kim is focused on direction. Knowing how much her call will rise or fall in step with the stock is her main concern. Notice that her delta tends to get bigger as the stock rises and smaller as the stock falls. As time passes, the delta gravitates toward 1.00 or 0, depending on whether the call is in-the-money (ITM) or out-of-the-money (OTM).
Theta
Option buying is a veritable race against the clock. With each passing day, the option loses theoretical value. Refer back to
Exhibit 4.3
. When three we

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falls. As time passes, the delta gravitates toward 1.00 or 0, depending on whether the call is in-the-money (ITM) or out-of-the-money (OTM).
Theta
Option buying is a veritable race against the clock. With each passing day, the option loses theoretical value. Refer back to
Exhibit 4.3
. When three weeks pass and the time to expiration decreases from 44 days to 23, what happens to the call value? If the stock price stays around its original level, theta will be responsible for a loss of about 30 percent of the premium. If Disney is at $35 with 23 days to expiration, the call will be worth $0.73. With a big enough move in either direction, however, theta matters much less.
With 23 days to expiration and Disney at $39, there is only 0.12 of time value—the premium paid over parity for the option. At that point, it is almost all delta exposure. Similarly, if the Disney stock price falls after three weeks to $33, the call will have only 0.10 of time value. Time decay is the least of Kim’s concerns if the stock makes a big move.
Vega
After delta and theta, vega is the next most influential contributor to Kim’s profit or peril. With Disney at $35.10, the 1.10 premium for the 35-strike call represents $1 of time value—all of which is vulnerable to changes in IV. The option’s 1.10 value returns an IV of about 19 percent, given the following inputs:
Stock: $35.10
Strike: 35
Days to expiration: 44
Interest: 5.25 percent
No dividend paid during this period
Consequently, the vega is 0.048. What does the 0.048 vega tell Kim? Given the preceding inputs, for each point the IV rises or falls, the option’s value gains or loses about $0.05.
Some of the inputs, however, will change. Kim anticipates that Disney will rise in price. She may be right or wrong. Either way, it is unlikely that the stock will remain exactly at $35.10 to option expiration. The only certainty is that time will pass.
Both price and time will change Kim’s vega exposure.
Exhibit 4.5
shows the changing vega of the 35 call as time and the underlying price change.
EXHIBIT 4.5
Disney 35 call price–time matrix–vega.
When comparing
Exhibit 4.5
to
Exhibit 4.3
, it’s easy to see that as the time value of the option declines, so does Kim’s exposure to vega. As time passes, vega gets smaller. And as the call becomes more in- or out-of-the-money, vega gets smaller. Since she plans to hold the position for around three weeks, she is not concerned about small fluctuations in IV in the interim.
If indeed the rise in price that Kim anticipates comes to pass, vega becomes even less of a concern. With 23 days to expiration and DIS at $37, the call value is 2.21. The vega is $0.018. If IV decreases as the stock price rises—a common occurrence—the adverse effect of vega will be minimal. Even if IV declines by 5 points, to a historically low IV for DIS, the call loses less than $0.10. That’s less than 5 percent of the new value of the option.
If dividend policy changes or the interest rate changes, the value of Kim’s call will be affected as well. Dividends are often fairly predictable. However, a large unexpected dividend payment can have a significant adverse impact on the value of the call. For example, if a surprise $3 dividend were announced, owning the stock would become greatly preferable to owning the call. This preference would be reflected in the call premium. This is a scenario that an experienced trader like Kim will realize is a possibility, although not a probability. Although she knows it can happen, she will not plan for such an event unless she believes it is likely to happen. Possible reasons for such a belief could be rumors or the company’s historically paying an irregular dividend.
Rho
For all intents and purposes, rho is of no concern to Kim. In recent years, interest rate changes have not been a major issue for option traders. In the Alan Greenspan years of Federal Reserve leadership, changes in the interest rate were usually announced at the regularly scheduled Federal Open Market Committee (FOMC) meetings, with but a few exceptions. Ben Bernanke, likewise, changed interest rates fairly predictably, when he made any rate changes at all. In these more stable periods, if there is no FOMC meeting scheduled during the life of the call, it’s unlikely that rates will change. Even if they do, the rho with 44 days to expiration is only 0.023. This means that if rates change by a whole percentage point—which is four times the most common incremental change—the call value will change by a little more than $0.02. In this case, this is an acceptable risk. With 23 days to expiration, the ATM 35 call has a rho of only 0.011.
Tweaking Greeks
With this position, some risks are of greater concern than others. Kim may want more exposure to some greeks and less to others. What if she is concerned that her forecasted price increase will take longer than three weeks? She may want less exposure to theta. What if she is particularly concerned about a decline in IV? She may wa


re of greater concern than others. Kim may want more exposure to some greeks and less to others. What if she is concerned that her forecasted price increase will take longer than three weeks? She may want less exposure to theta. What if she is particularly concerned about a decline in IV? She may want to decrease her vega. Conversely, she may believe IV will rise and therefore want to increase her vega.
Kim has many ways at her disposal to customize her greeks. All of her alternatives come with trade-offs. She can buy more calls, increasing her greek positions in exact proportion. She can buy or sell stock or options against her call, creating a spread. The simplest way to alter her exposure to option greeks is to choose a different call to buy. Instead of buying the ATM call, Kim can buy a call with a different relationship to the current stock price.
Long OTM Call
Kim can reduce her exposure to theta and vega by buying an OTM call. The trade-off here is that she also reduces her immediate delta exposure. Depending on how much Kim believes Disney will rally, this may or may not be a viable trade-off. Imagine that instead of buying one Disney March 35 call, Kim buys one Disney March 37.50 call, for 0.20.
There are a few observations to be made about this alternative position. First, the net premium, and therefore overall risk, is much lower, 0.20 instead of 1.10. From an expiration standpoint, the breakeven at expiration is $37.70 (the strike price plus the call premium). Since Kim plans on exiting the position after about three weeks, the exact break-even point at the expiration of the contract is irrelevant. But the concept is the same: the stock needs to rise significantly.
Exhibit 4.6
shows how Kim’s concerns translate into greeks.
EXHIBIT 4.6
Greeks for Disney 35 and 37.50 calls.
35 Call
37.50 Call
Delta
0.57
0.185
Gamma
0.166
0.119
Theta
−0.013
−0.007
Vega
0.048
0.032
Rho
0.023
0.007
This table compares the ATM call with the OTM call. Kim can reduce her theta to half that of the ATM call position by purchasing an OTM. This is certainly a favorable difference. Her vega is lower with the 37.50 call, too. This may or may not be a favorable difference. That depends on Kim’s opinion of IV.
On the surface, the disparity in delta appears to be a highly unfavorable trade-off. The delta of the 37.50 call is less than one third of the delta of the 35 call, and the whole motive for entering into this trade is to trade direction! Although this strategy is very delta oriented, its core is more focused on gamma and theta.
The gamma of the 37.50 call is about 72 percent that of the 35 call. But the theta of the 37.50 call is about half that of the 35 call. Kim is improving her gamma/theta relationship by buying the OTM, but with the call being so far out-of-the-money and so inexpensive, the theta needs to be taken with a grain of salt. It is ultimately gamma that will make or break this delta play.
The price of the option is 0.20—a rather low premium. In order for the call to gain in value, delta has to go to work with help from gamma. At this point, the delta is small, only 0.185. If Kim’s forecast is correct and there is a big move upward, gamma will cause the delta to increase, and therefore also the premium to increase exponentially. The call’s sensitivity to gamma, however, is dynamic.
Exhibit 4.7
shows how the gamma of the 37.50 call changes as the stock price moves over time. At any point in time, gamma is highest when the call is ATM. However, so is theta. Kim wants to reap as much benefit from gamma as possible while minimizing her exposure to theta. Ideally, she wants Disney to rally through the strike price—through the high gamma and back to the low theta. After three weeks pass, with 23 days until expiration, if Disney is at $37 a share, the gamma almost doubles, to 0.237. When the call is ATM, the delta increases at its fastest rate. As Disney rises above the strike, the gamma figures in the table begin to decline.
EXHIBIT 4.7
Disney 37.50 call price–time matrix–gamma.
Gamma helps as the stock price declines, too.
Exhibit 4.8
shows the effect of time and gamma on the delta of the 37.50 call.
EXHIBIT 4.8
Disney 37.50 call price–time matrix–delta.
The effect of gamma is readily observable, as the delta at any point in time is always higher at higher stock prices and lower at lower stock prices. Kim benefits greatly when the delta grows from its initial level of 0.185 to above 0.50—above the point of being at-the-money. If the stock moves lower, gamma helps take away the pain of the price decline by decreasing the delta.
While delta, gamma, and theta occupy Kim’s thoughts, it is ultimately dollars and cents that matter. She needs to translate her study of the greeks into cold, hard cash.
Exhibit 4.9
shows the theoretical values of the 37.50 call.
EXHIBIT 4.9
Disney 37.50 call price–time matrix–value.
The sooner the price rise occurs, the better. It means less time for theta to eat away profits. If Kim must


matter. She needs to translate her study of the greeks into cold, hard cash.
Exhibit 4.9
shows the theoretical values of the 37.50 call.
EXHIBIT 4.9
Disney 37.50 call price–time matrix–value.
The sooner the price rise occurs, the better. It means less time for theta to eat away profits. If Kim must hold the position for the entire three weeks, she needs a good pop in the stock to make it worth her while. At a $37 share price, the call is worth about 0.50, assuming all other market influences remain constant. That’s about a 150 percent profit. At $38,
Exhibit 4.9
reveals the call value to be 1.04. That’s a 420 percent profit.
On one hand, it’s hard for a trader like Kim not to get excited about the prospect of making 420 percent on an 8 percent move in a stock. On the other hand, Kim has to put things in perspective. When the position is established, the call has a 0.185 delta. By the trader’s definition of delta, that means the call is estimated to have about an 18.5 percent chance of expiring in-the-money. More than four out of five times, this position will be trading below the strike at expiration.
Although Kim is not likely to hold the position until expiration, this observation tells her something: she’s starting in the hole. She is more likely to lose than to win. She needs to be compensated well for her risk on the winners to make up for the more prevalent losers.
Buying OTM calls can be considered more speculative than buying ITM or ATM calls. Unlike what the at-expiration diagrams would lead one to believe, OTM calls are not simply about direction. There’s a bit more to it. They are really about gamma, time, and the magnitude of the stock’s move (volatility). Long OTM calls require a big move in the right direction for gamma to do its job.
Long ITM Call
Kim also has the alternative to buy an ITM call. Instead of the 35 or 37.50 call, she can buy the 32.50. The 32.50 call shares some of the advantages the 37.50 call has over the 35 call, but its overall greek characteristics make it a very different trade from the two previous alternatives.
Exhibit 4.10
shows a comparison of the greeks of the three different calls.
EXHIBIT 4.10
Greeks for Disney 32.50, 35, and 37.50 calls.
Like the 37.50 call, the 32.50 has a lower gamma, theta, and vega than the ATM 35-strike call. Because the call is ITM, it has a higher delta: 0.862. In this example, Kim can buy the 32.50 call for 3. That’s 0.40 over parity (3 − [35.10 − 32.50] = 0.40). There is not much time value, but more than the 37.50 call has. Thus, theta is of some concern. Ultimately, the ITMs have 0.40 of time value to lose compared with the 0.20 of the OTM calls. Vega is also of some concern, but not as much as in the other alternatives because the vega of the 32.50 is lower than the 35s or the 37.50s. Gamma doesn’t help much as the stock rallies—it will get smaller as the stock price rises. Gamma will, however, slow losses somewhat if the stock declines by decreasing delta at an increasing rate.
In this case, the greek of greatest consequence is delta—it is a more purely directional play than the other alternatives discussed.
Exhibit 4.11
shows the matrix of the delta of the 32.50 call.
EXHIBIT 4.11
Disney 32.50 call price–time matrix–delta.
Because the call starts in-the-money and has a relatively low gamma, the delta remains high even if Disney declines significantly. Gamma doesn’t really kick in until the stock retreats enough to bring the call closer to being at-the-money. At that point, the position will have suffered a big loss, and the higher gamma is of little comfort.
Kim’s motivation for selecting the ITM call above the ATM and OTM calls would be increased delta exposure. The 0.86 delta makes direction the most important concern right out of the gate.
Exhibit 4.12
shows the theoretical values of the 32.50 call.
EXHIBIT 4.12
Disney 32.50 call price–time matrix–value.
Small directional moves contribute to significant leveraged gains or losses. From share price $35 to $36, the call gains 0.90—from 2.91 to 3.81—about a 30 percent gain. However, from $35 to $34, the call loses 0.80, or 27 percent. With only 0.40 of time value, the nondirectional greeks (theta, gamma, and vega) are a secondary consideration.
If this were a deeper ITM call, the delta would start out even higher, closer to 1.00, and the other relevant greeks would be closer to zero. The deeper ITM a call, the more it acts like the stock and the less its option characteristics (greeks) come into play.
Long ATM Put
The beauty of the free market is that two people can study all the available information on the same stock and come up with completely different outlooks. First of all, this provides for entertaining television on the business-news channels when the network juxtaposes an outspoken bullish analyst with an equally unreserved bearish analyst. But differing opinions also make for a robust marketplace. Differing opinions are the oil that greases the machine that is price discove


ides for entertaining television on the business-news channels when the network juxtaposes an outspoken bullish analyst with an equally unreserved bearish analyst. But differing opinions also make for a robust marketplace. Differing opinions are the oil that greases the machine that is price discovery. From a market standpoint, it’s what makes the world go round.
It is possible that there is another trader, Mick, in the market studying Disney, who arrives at the conclusion that the stock is overpriced. Mick believes the stock will decline in price over the next three weeks. He decides to buy one Disney March 35 put at 0.80. In this example, March has 44 days to expiration.
Mick initiates this long put position to gain downside exposure, but along with his bearish position comes option-specific risk and opportunity. Mick is buying the same month and strike option as Kim did in the first example of this chapter: the March 35 strike. Despite the different directional bias, Mick’s position and Kim’s position share many similarities.
Exhibit 4.13
offers a comparison of the greeks of the Disney March 35 call and the Disney March 35 put.
EXHIBIT 4.13
Greeks for Disney 35 call and 35 put.
Call
Put
Delta
0.57
−0.444
Gamma
0.166
0.174
Theta
−0.013
−0.009
Vega
0.048
0.048
Rho
0.023
−0.015
The first comparison to note is the contrasting deltas. The put delta is negative, in contrast to the call delta. The absolute value of the put delta is close to 1.00 minus the call delta. The put is just slightly OTM, so its delta is just under 0.50, while that of the call is just over 0.50. The disparate, yet related deltas represent the main difference between these two trades.
The difference between the gamma of the 35 put and that of the corresponding call is fairly negligible: 0.174 versus 0.166, respectively. The gamma of this ATM put will enter into the equation in much the same way as the gamma of the ATM call. The put’s negative delta will become more negative as the stock declines, drawing closer to −1.00. It will get less negative as the stock price rises, drawing closer to zero. Gamma is important here, because it helps the delta. Delta, however, still remains the most important greek.
Exhibit 4.14
illustrates how the 35 put delta changes as time and price change.
EXHIBIT 4.14
Disney 35 put price–time matrix–delta.
Since this put is ATM, it starts out with a big enough delta to offer the directional exposure Mick desires. The delta can change, but gamma ensures that it always changes in Mick’s favor.
Exhibit 4.15
shows how the value of the 35 put changes with the stock price.
EXHIBIT 4.15
Disney 35 put price–time matrix–value.
Over time, a decline of only 10 percent in the stock yields high percentage returns. This is due to the leveraged directional nature of this trade—delta.
While the other greeks are not of primary concern, they must be monitored. At the onset, the 0.80 premium is all time value and, therefore subject to the influences of time decay and volatility. This is where trading greeks comes into play.
Conventional trading wisdom says, “Cut your losses early, and let your profits run.” When trading a stock, that advice is intellectually easy to understand, although psychologically difficult to follow. Buyers of options, especially ATM options, must follow this advice from the standpoint of theta. Options are decaying assets. The time premium will be zero at expiration. ATMs decay at an increasing nonlinear rate. Exiting a long position before getting too close to expiration can cut losses caused by an increasing theta. When to cut those losses, however, will differ from trade to trade, situation to situation, and person to person.
When buying options, accepting some loss of premium due to time decay should be part of the trader’s plan. It comes with the territory. In this example, Mick is willing to accept about three weeks of erosion. Mick needs to think about what his put will be worth, not just if the underlying rises or falls but also if it doesn’t move at all. At the time the position is established, the theta is 0.009, just under a penny. If Disney share price is unchanged when three weeks pass, his theta will be higher.
Exhibit 4.16
shows how thetas and theoretical values change over time if DIS stock remains at $35.10.
EXHIBIT 4.16
Disney 35 put—thetas and theoretical values.
Mick needs to be concerned not only about what the theta is now but what it will be when he plans on exiting the position. His plan is to exit the trade in about three weeks, at which point the put theta will be −0.013. If he amortizes his theta over this three-week period, he theoretically loses an average of about 0.01 a day during this time if nothing else changes. The average daily theta is calculated here by subtracting the value of the put at 23 days to expiration from its value when the trade was established to find the loss of premium attributed to time decay, then dividing by the number of days until expiration.
Since th


his time if nothing else changes. The average daily theta is calculated here by subtracting the value of the put at 23 days to expiration from its value when the trade was established to find the loss of premium attributed to time decay, then dividing by the number of days until expiration.
Since the theta doesn’t change much over the first three weeks, Mick can eyeball the theta rather easily. As expiration approaches and theta begins to grow more quickly, he’ll need to do the math.
At nine days to expiration, the theoretical value of Mick’s put is about 0.35, assuming all other variables are held constant. By that time, he will have lost 0.45 (0.80 − 0.35) due to erosion over the 35-day period he held the position if the stock hasn’t moved. Mick’s average daily theta during that period is about 0.0129 (0.45 ÷ 35). The more time he holds the trade, the greater a concern is theta. Mick must weigh his assessment of the likelihood of the option’s gaining value from delta against the risk of erosion. If he holds the trade for 35 days, he must make 0.0129 on average per day from delta to offset theta losses. If the forecast is not realized within the expected time frame or if the forecast changes, Mick needs to act fast to curtail average daily theta losses.
Finding the Right Risk
Mick could lower the theta of his position by selecting a put with a greater number of days to expiration. This alternative has its own set of trade-offs: lower gamma and higher vega than the 44-day put. He could also select an ITM put or an OTM put. Like Kim’s call alternatives, the OTM put would have less exposure to time decay, lower vega, lower gamma, and a lower delta. It would have a lower premium, too. It would require a bigger price decline than the ATM put and would be more speculative.
The ITM put would also have lower theta, vega, and gamma, but it would have a higher delta. It would take on more of the functionality of a short stock position in much the same way that Kim’s ITM call alternative did for a long stock position. In its very essence, however, an option trade, ITM or otherwise, is still fundamentally different than a stock trade.
Stock has a 1.00 delta. The delta of a stock never changes, so it has zero gamma. Stock is not subject to time decay and has no volatility component to its pricing. Even though ITM options have deltas that approach 1.00 and other greeks that are relatively low, they have two important differences from an equity. The first is that the greeks of options are dynamic. The second is the built-in leverage feature of options.
The relationship of an option’s strike price to the stock price can change constantly. Options that are ITM now may be OTM tomorrow and vice versa. Greeks that are not in play at the moment may be later. Even if there is no time value in the option now because it is so far away-from-the-money, there is the potential for time premium to become a component of the option’s price if the stock moves closer to the strike price. Gamma, theta, and vega always have the potential to come into play.
Since options are leveraged by nature, small moves in the stock can provide big profits or big losses. Options can also curtail big losses if used for hedging. Long option positions can reap triple-digit percentage gains quickly with a favorable move in the underlying. Even though 100 percent of the premium can be lost just as easily, one option contract will have far less nominal exposure than a similar position in the stock.
It’s All About Volatility
What are Kim and Mick really trading? Volatility. The motivation for buying an option as opposed to buying or shorting the stock is volatility. To some degree, these options have exposure to both flavors of volatility—implied volatility and historical volatility (HV). The positions in each of the examples have positive vega. Their values are influenced, in part, by IV. Over time, IV begins to lose its significance if the option is no longer close to being at-the-money.
The main objective of each of these trades is to profit from the volatility of the stock’s price movement, called future stock volatility or future realized volatility. The strategies discussed in this chapter are contingent on volatility being one directional. The bigger the move in the trader’s forecasted direction the better. Volatility in the form of an adverse directional move results in a decline in premium. The gamma in these long option positions makes volatility in the right direction more beneficial and volatility in the wrong direction less costly.
This phenomenon is hardly unique to the long call and the long put. Although some basic strategies, such as the ones studied in this chapter, depend on a particular direction, many don’t. Except for interest rate strategies and perhaps some arbitrage strategies, all option trades are volatility trades in one way or another. In general, option strategies can be divided into two groups: volatility-buying strategies and vol


in this chapter, depend on a particular direction, many don’t. Except for interest rate strategies and perhaps some arbitrage strategies, all option trades are volatility trades in one way or another. In general, option strategies can be divided into two groups: volatility-buying strategies and volatility-selling strategies. The following is a breakdown of common option strategies into categories of volatility-buying strategies and volatility-selling strategies:
Volatility-Selling Strategies
Volatility-Buying Strategies
Short Call, Short Put, Covered Call, Covered Put, Bull Call Spread, Bear Call Spread, Bull Put Spread, Bear Put Spread, Short Straddle, Short Strangle, Guts, Ratio Call Spread, Calendar, Butterfly, Iron Butterfly, Broken-Wing Butterfly, Condor, Iron Condor, Diagonals, Double Diagonals, Risk Reversals/Collars.
Long Call, Long Put, Bull Call Spread, Bear Call Spread, Bull Put Spread, Bear Put Spread, Long Straddle, Long Strangle, Guts, Back Spread, Calendar, Butterfly, Iron Butterfly, Broken-Wing Butterfly, Condor, Iron Condor, Diagonals, Double Diagonals, Risk Reversals/Collars.
Long option strategies appear in the volatility-buying group because they have positive gamma and positive vega. Short option strategies appear in the volatility-selling group because of negative gamma and vega. There are some strategies that appear in both groups—for example, the butterfly/condor family, which is typically associated with income generation. These particular volatility strategies are commonly instituted as volatility-selling strategies. However, depending on whether the position is bought or sold and where the stock price is in relation to the strike prices, the position could fall into either group. Some strategies, like the vertical spread family—bull and bear call and put spreads—and risk reversal/collar spreads naturally fall into either category, depending on where the stock is in relation to the strikes. The calendar spread family is unique in that it can have characteristics of each group at the same time.
Direction Neutral, Direction Biased, and Direction Indifferent
As typically traded, volatility-selling option strategies are direction neutral. This means that the position has the greatest results if the underlying price remains in a range—that is, neutral. Although some option-selling strategies—for example, a naked put—may have a positive or negative delta in the short term, profit potential is decidedly limited. This means that if traders are expecting a big move, they are typically better off with option-buying strategies.
Option-buying strategies can be either direction biased or direction indifferent. Direction-biased strategies have been shown throughout this chapter. They are delta trades. Direction-indifferent strategies are those that benefit from increased volatility in the underlying but where the direction of the move is irrelevant to the profitability of the trade. Movement in either direction creates a winner.
Are You a Buyer or a Seller?
The question is: which is better, selling volatility or buying volatility? I have attended option seminars with instructors (many of whom I regard with great respect) teaching that volatility-selling strategies, or income-generating strategies, are superior to buying options. I also know option gurus that tout the superiority of buying options. The answer to the question of which is better is simple: it’s all a matter of personal preference.
When I began trading on the floor of Chicago Board Options Exchange (CBOE) in the 1990s, I quickly became aware of a dichotomy among my market-making peers. Those making markets on the floor of the exchange at that time were divided into two groups: teenie buyers and teenie sellers.
Teenie Buyers
Before options traded in decimals (dollars and cents) like they do today, the lowest price increment in which an option could be traded was one sixteenth of a dollar—a
teenie
. Teenie buyers were market makers who would buy back OTM options at one sixteenth to eliminate short positions. They would sometimes even initiate long OTM option positions at a teenie, too. The focus of the teenie-buyer school of thought was the fact that long options have unlimited reward, while short options have unlimited risk. An option purchased so far OTM that it was offered at one sixteenth is unlikely to end up profitable, but it’s an inexpensive lottery ticket. At worst, the trader can only lose a teenie. Teenie buyers felt being short OTM options that could be closed by paying a sixteenth was an unreasonable risk.
Teenie Sellers
Teenie sellers, however, focused on the fact that options offered at one sixteenth were far enough OTM that they were very likely to expire worthless. This appears to be free money, unless the unexpected occurs, in which case potential losses can be unlimited. Teenie sellers would routinely save themselves $6.25 (one sixteenth of a dollar per contract representing 100 shares) by selling their long OTMs a


they were very likely to expire worthless. This appears to be free money, unless the unexpected occurs, in which case potential losses can be unlimited. Teenie sellers would routinely save themselves $6.25 (one sixteenth of a dollar per contract representing 100 shares) by selling their long OTMs at a teenie to close the position. They sometimes would even initiate short OTM contracts at one sixteenth.
These long-option or short-option biases hold for other types of strategies as well. Volatility-selling positions, such as the iron condor, can be constructed to have limited risk. The paradigm for these strategies is they tend to produce winners more often than not. But when the position loses, the trader loses more than he would stand to profit if the trade worked out favorably.
Herein lies the issue of preference. Long-option traders would rather trade Babe Ruth–style. For years, Babe Ruth was the record holder for the most home runs. At the same time, he was also the record holder for the most strikeouts. The born fighters that are option buyers accept the fact that they will have more strikeouts, possibly many more strikeouts, than winning trades. But the strategy dictates that the profit on one winner more than makes up for the string of small losers.
Short-option traders, conversely, like to have everything cool and copacetic. They like the warm and fuzzy feeling they get from the fact that month after month they tend to generate winners. The occasional loser that nullifies a few months of profits is all part of the game.
Options and the Fair Game
There may be a statistical advantage to buying stock as opposed to shorting stock, because the market has historically had a positive annualized return over the long run. A statistical advantage to being either an option buyer or an option seller, however, should not exist in the long run, because the option market prices IV. Assuming an overall efficient market for pricing volatility into options, there should be no statistical advantage to systematically buying or selling options.
1
Consider a game consisting of one six-sided die. Each time a one, two, or three is rolled, the house pays the player $1. Each time a four, five, or six is rolled, the house pays zero. What is the most a player would be willing to pay to play this game? If the player paid nothing, the house would be at a tremendous disadvantage, paying $1 50 percent of the time and nothing the other 50 percent of the time. This would not be a fair game from the house’s perspective, as it would collect no money. If the player paid $1, the player would get his dollar back when one, two, or three came up. Otherwise, he would lose his dollar. This is not a fair game from the player’s perspective.
The chances of winning this game are 3 out of 6, or 50–50. If this game were played thousands of times, one would expect to receive $1 half the time and receive nothing the other half of the time. The average return per roll one would expect to receive would be $0.50, that’s ($1 × 50 percent + $0 × 50 percent). This becomes a fair game with an entrance fee of $0.50.
Now imagine a similar game in which a six-sided die is rolled. This time if a one is rolled, the house pays $1. If any other number is rolled, the house pays nothing. What is a fair price to play this game? The same logic and the same math apply. There is a
percent chance of a one coming up and the player receiving $1. And there is a
percent chance of each of the other five numbers being rolled and the player receiving nothing. Mathematically, this translates to:
percent
percent). Fair value for a chance to play this game is about $0.1667 per roll.
The fair game concept applies to option prices as well. The price of the game, or in this case the price of the option, is determined by the market in the form of IV. The odds are based on the market’s expectations of future volatility. If buying options offered a superior payout based on the odds of success, the market would put upward pressure on prices until this arbitrage opportunity ceased to exist. It’s the same for selling volatility. If selling were a fundamentally better strategy, the market would depress option prices until selling options no longer produced a way to beat the odds. The options market will always equalize imbalances.
Note
1
. This is not to say that unique individual opportunities do not exist for overpriced or underpriced options, only that options are not overpriced or underpriced in general. Thus, neither an option-selling nor option-buying methodology should provide an advantage.


CHAPTER 5
An Introduction to Volatility-Selling Strategies
Along with death and taxes, there is one other fact of life we can all count on: the time value of all options ultimately going to zero. What an alluring concept! In a business where expected profits can be thwarted by an unexpected turn of events, this is one certainty traders can count on. Like all certainties in the financial world, there is a way to profit from this fact, but it’s not as easy as it sounds. Alas, the potential for profit only exists when there is risk of loss.
In order to profit from eroding option premiums, traders must implement option-selling strategies, also known as volatility-selling strategies. These strategies have their own set of inherent risks. Selling volatility means having negative vega—the risk of implied volatility rising. It also means having negative gamma—the risk of the underlying being too volatile. This is the nature of selling volatility. The option-selling trader does not want the underlying stock to move—that is, the trader wants the stock to be less volatile. That is the risk.
Profit Potential
Profit for the volatility seller is realized in a roundabout sort of way. The reward for low volatility is achieved through time decay. These strategies have positive theta. Just as the volatility-buying strategies covered in Chapter 4 had time working against them, volatility-selling strategies have time working in their favor. The trader is effectively paid to assume the risk of movement.
Gamma-Theta Relationship
There exists a trade-off between gamma and theta. Long options have positive gamma and negative theta. Short options have negative gamma and positive theta. Positions with greater gamma, whether positive or negative, tend to have greater theta values, negative or positive. Likewise, lower absolute values for gamma tend to go hand in hand with lower absolute values for theta. The gamma-theta relationship is the most important consideration with many types of strategies. Gamma-theta is often the measurement with the greatest influence on the bottom line.
Greeks and Income Generation
With volatility-selling strategies (sometimes called income-generating strategies), greeks are often overlooked. Traders simply dismiss greeks as unimportant to this kind of trade. There is some logic behind this reasoning. Time decay provides the profit opportunity. In order to let all of time premium erode, the position must be held until expiration. Interim changes in implied volatility are irrelevant if the position is held to term. The gamma-theta loses some significance if the position is held until expiration, too. The position has either passed the break-even point on the at-expiration diagram, or it has not. Incremental daily time decay–related gains are not the ultimate goal. The trader is looking for all the time premium, not portions of it.
So why do greeks matter to volatility sellers? Greeks allow traders to be flexible. Consider short-term-momentum stock traders. The traders buy a stock because they believe it will rise over the next month. After one week, if unexpected bearish news is announced causing the stock to break through its support lines, the traders have a decision to make. Short-term speculative traders very often choose to cut their losses and exit the position early rather than risk a larger loss hoping for a recovery.
Volatility-selling option traders are often faced with the same dilemma. If the underlying stays in line with the traders’ forecast, there is little to worry about. But if the environment changes, the traders have to react. Knowing the greeks for a position can help traders make better decisions if they plan to close the position before expiration.
Naked Call
A naked call is when a trader shorts a call without having stock or other options to cover or protect it. Since the call is uncovered, it is one of the riskier trades a trader can make. Recall the at-expiration diagram for the naked call from Chapter 1,
Exhibit 1.3
: Naked TGT Call. Theoretically, there is limited reward and unlimited risk. Yet there are times when experienced traders will justify making such a trade. When a stock has been trading in a range and is expected to continue doing so, traders may wait until it is near the top of the channel, where there is resistance, and then short a call.
For example, a trader, Brendan, has been studying a chart of Johnson & Johnson (JNJ). Brendan notices that for a few months the stock has trading been in a channel between $60 and $65. As he observes Johnson & Johnson beginning to approach the resistance level of $65 again, he considers selling a call to speculate on the stock not rising above $65. Before selling the call, Brendan consults other technical analysis tools, like ADX/DMI, to confirm that there is no trend present. ADX/DMI is used by some traders as a filter to determine the strength of a trend and whether the stock is overbought or oversold. In this case, the indicator

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above $65. Before selling the call, Brendan consults other technical analysis tools, like ADX/DMI, to confirm that there is no trend present. ADX/DMI is used by some traders as a filter to determine the strength of a trend and whether the stock is overbought or oversold. In this case, the indicator shows no strong trend present. Brendan then performs due diligence. He studies the news. He looks for anything specific that could cause the stock to rally. Is the stock a takeover target? Brendan finds nothing. He then does earnings research to find out when they will be announced, which is not for almost two more months.
Next, Brendan pulls up an option chain on his computer. He finds that with the stock trading around $64 per share, the market for the November 65 call (expiring in four weeks) is 0.66 bid at 0.68 offer. Brendan considers when Johnson & Johnson’s earnings report falls. Although recent earnings have seldom been a major concern for Johnson & Johnson, he certainly wants to sell an option expiring before the next earnings report. The November fits the mold. Brendan sells ten of the November 65 calls at the bid price of 0.66.
Brendan has a rather straightforward goal. He hopes to see Johnson & Johnson shares remain below $65 between now and expiration. If he is right, he stands to make $660. If he is wrong?
Exhibit 5.1
shows how Brendan’s calls hold up if they are held until expiration.
EXHIBIT 5.1
Naked Johnson & Johnson call at expiration.
Considering the risk/reward of this trade, Brendan is rightfully concerned about a big upward move. If the stock begins to rally, he must be prepared to act fast. Brendan must have an idea in advance of what his pain threshold is. In other words, at what price will he buy back his calls and take a loss if Johnson & Johnson moves adversely?
He decides he will buy all 10 of his calls back at 1.10 per contract if the trade goes against him. (1.10 is an arbitrary price used for illustrative purposes. The actual price will vary, based on the situation and the risk tolerance of the trader. More on when to take profits and losses is discussed in future chapters.) He may choose to enter a good-till-canceled (GTC) stop-loss order to buy back his calls. Or he may choose to monitor the stock and enter the order when he sees the calls offered at 1.10—a mental stop order. What Brendan needs to know is: How far can the stock price advance before the calls are at 1.10?
Brendan needs to examine the greeks of this trade to help answer this question.
Exhibit 5.2
shows the hypothetical greeks for the position in this example.
EXHIBIT 5.2
Greeks for short Johnson & Johnson 65 call (per contract).
Delta
−0.34
Gamma
−0.15
Theta
0.02
Vega
−0.07
The short call has a negative delta. It also has negative gamma and vega, but it has positive time decay (theta). As Johnson & Johnson ticks higher, the delta increases the nominal value of the call. Although this is not a directional trade per se, delta is a crucial element. It will have a big impact on Brendan’s expectations as to how high the stock can rise before he must take his loss.
First, Brendan considers how much the option price can move before he covers. The market now is 0.66 bid at 0.68 offer. To buy back his calls at 1.10, they must be offered at 1.10. The difference between the offer now and the offer price at which Brendan will cover is 0.42 (that’s 1.10 − 0.68). Brendan can use delta to convert the change in the ask prices into a stock price change. To do so, Brendan divides the change in the option price by the delta.
The −0.34 delta indicates that if JNJ rises $1.24, the calls should be offered at 1.10.
Brendan takes note that the bid-ask spreads are typically 0.01 to 0.03 wide in near-term Johnson & Johnson options trading under 1.00. This is not necessarily the case in other option classes. Less liquid names have wider spreads. If the spreads were wider, Brendan would have more slippage. Slippage is the difference between the assumed trade price and the actual price of the fill as a product of the bid-ask spread. It’s the difference between theory and reality. If the bid-ask spread had a typical width of, say, 0.70, the market would be something more like 0.40 bid at 1.10 offer. In this case, if the stock moved even a few cents higher, Brendan could not buy his calls back at his targeted exit price of 1.10. The tighter markets provide lower transaction costs in the form of lower slippage. Therefore, there is more leeway if the stock moves adversely when there are tighter bid-ask option spreads.
But just looking at delta only tells a part of the story. In reality, the delta does not remain constant during the price rise in Johnson & Johnson but instead becomes more negative. Initially, the delta is −0.34 and the gamma is −0.15. After a rise in the stock price, the delta will be more negative by the amount of the gamma. To account for the entire effect of direction, Brendan needs to take both delta and gamma into account. He


& Johnson but instead becomes more negative. Initially, the delta is −0.34 and the gamma is −0.15. After a rise in the stock price, the delta will be more negative by the amount of the gamma. To account for the entire effect of direction, Brendan needs to take both delta and gamma into account. He needs to estimate the average delta based on gamma during the stock price move. The formula for the change in stock price is
Taking into account the effect of gamma as well as delta, Johnson & Johnson needs to rise only $1.01, in order for Brendan’s calls to be offered at his stop-loss price of 1.10.
While having a predefined price point to cover in the event the underlying rises is important, sometimes traders need to think on their feet. If material news is announced that changes the fundamental outlook for the stock, Brendan will have to adjust his plan. If the news leads Brendan to become bullish on the stock, he should exit the trade at once, taking a small loss now instead of the bigger loss he would expect later. If the trader is uncertain as to whether to hold or close the position, the Would I Do It Now? rule is a useful rule of thumb.
Would I Do It Now? Rule
To follow this rule, ask yourself, “If I did not already have this position, would I do it now? Would I establish the position at the current market prices, given the current market scenario?” If the answer is no, then the solution is simple: Exit the trade.
For example, if after one week material news is released and Johnson & Johnson is trading higher, at $64.50 per share, and the November 65 call is trading at 0.75, Brendan must ask himself, based on the price of the stock and all known information, “If I were not already short the calls, would I short them now at the current price of 0.75, with the stock trading at $64.50?”
Brendan’s opinion of the stock is paramount in this decision. If, for example, based on the news that was announced he is now bullish, he would likely not want to sell the calls at 0.75—he only gets $0.09 more in option premium and the stock is 0.50 closer to the strike. If, however, he is not bullish, there is more to consider.
Theta can be of great use in decision making in this situation. As the number of days until expiration decreases and the stock approaches $65 (making the option more at-the-money), Brendan’s theta grows more positive.
Exhibit 5.3
shows the theta of this trade as the underlying rises over time.
EXHIBIT 5.3
Theta of Johnson & Johnson.
When the position is first established, positive theta comforts Brendan by showing that with each passing day he gets a little closer to his goal—to have the 65 calls expire out-of-the-money (OTM) and reap a profit of the entire 66-cent premium. Theta becomes truly useful if the position begins to move against him. As Johnson & Johnson rises, the trade gets more precarious. His negative delta increases. His negative gamma increases. His goal becomes more out of reach. In conjunction with delta and gamma, theta helps Brendan decide whether the risk is worth the reward.
In the new scenario, with the stock at $64.50, Brendan would collect $18 a day (1.80 × 10 contracts). Is the risk of loss in the short run worth earning $18 a day? With Johnson & Johnson at $64.50, would Brendan now short 10 calls at 0.75 to collect $18 a day, knowing that each day may bring a continued move higher in the stock? The answer to this question depends on Brendan’s assessment of the risk of the underlying continuing its ascent. As time passes, if the stock remains closer to the strike, the daily theta rises, providing more reward. Brendan must consider that as theta—the reward—rises, so does gamma: a risk factor.
A small but noteworthy risk is that implied volatility could rise. The negative vega of this position would, then, adversely affect the profitability of this trade. It will make Brendan’s 1.10 cover-point approach faster because it makes the option more expensive. Vega is likely to be of less consequence because it would ultimately take the stock’s rising though the strike price for the trade to be a loser at expiration.
Short Naked Puts
Another trader, Stacie, has also been studying Johnson & Johnson. Stacie believes Johnson & Johnson is on its way to test the $65 resistance level yet again. She believes it may even break through $65 this time, based on strong fundamentals. Stacie decides to sell naked puts. A naked put is a short put that is not sold in conjunction with stock or another option.
With the stock around $64, the market for the November 65 put is 1.75 bid at 1.80. Stacie likes the fact that the 65 puts are slightly in-the-money (ITM) and thus have a higher delta. If her price rise comes sooner than expected, the high delta may allow her to take a profit early. Stacie sells 10 puts at 1.75.
In the best-case scenario, Stacie retains the entire 1.75. For that to happen, she will need to hold this position until expiration and the stock will have to rise to be trading above the


comes sooner than expected, the high delta may allow her to take a profit early. Stacie sells 10 puts at 1.75.
In the best-case scenario, Stacie retains the entire 1.75. For that to happen, she will need to hold this position until expiration and the stock will have to rise to be trading above the 65 strike. Logically, Stacie will want to do an at-expiration analysis.
Exhibit 5.4
shows Stacie’s naked put trade if she holds it until expiration.
EXHIBIT 5.4
Naked Johnson & Johnson put at expiration.
While harvesting the entire premium as a profit sounds attractive, if Stacie can take the bulk of her profit early, she’ll be happy to close the position and eliminate her risk—nobody ever went broke taking a profit. Furthermore, she realizes that her outlook may be wrong: Johnson & Johnson may decline. She may have to close the position early—maybe for a profit, maybe for a loss. Stacie also needs to study her greeks.
Exhibit 5.5
shows the greeks for this trade.
EXHIBIT 5.5
Greeks for short Johnson & Johnson 65 put (per contract).
Delta
0.65
Gamma
−0.15
Theta
0.02
Vega
−0.07
The first item to note is the delta. This position has a directional bias. This bias can work for or against her. With a positive 0.65 delta per contract, this position has a directional sensitivity equivalent to being long around 650 shares of the stock. That’s the delta × 100 shares × 10 contracts.
Stacie’s trade is not just a bullish version of Brendan’s. Partly because of the size of the delta, it’s different—specific directional bias aside. First, she will handle her trade differently if it is profitable.
For example, if over the next week or so Johnson & Johnson rises $1, positive delta and negative gamma will have a net favorable effect on Stacie’s profitability. Theta is small in comparison and won’t have too much of an effect. Delta/gamma will account for a decrease in the put’s theoretical value of about $0.73. That’s the estimated average delta times the stock move, or [0.65 + (–0.15/2)] × 1.00.
Stacie’s actual profit would likely be less than 0.73 because of the bid-ask spread. Stacie must account for the fact that the bid-ask is 0.05 wide (1.75–1.80). Because Stacie would buy to close this position, she should consider the 0.73 price change relative to the 1.80 offer, not the 1.75 trade price—that is, she factors in a nickel of slippage. Thus, she calculates, that the puts will be offered at 1.07 (that’s 1.80 − 0.73) when the stock is at $65. That is a gain of $0.68.
In this scenario, Stacie should consider the Would I Do It Now? rule to guide her decision as to whether to take her profit early or hold the position until expiration. Is she happy being short ten 65 puts at 1.07 with Johnson & Johnson at $65? The premium is lower now. The anticipated move has already occurred, and she still has 28 days left in the option that could allow for the move to reverse itself. If she didn’t have the trade on now, would she sell ten 65 puts at 1.07 with Johnson & Johnson at $65? Based on her original intention, unless she believes strongly now that a breakout through $65 with follow-through momentum is about to take place, she will likely take the money and run.
Stacie also must handle this trade differently from Brendan in the event that the trade is a loser. Her trade has a higher delta. An adverse move in the underlying would affect Stacie’s trade more than it would Brendan’s. If Johnson & Johnson declines, she must be conscious in advance of where she will cover.
Stacie considers both how much she is willing to lose and what potential stock-price action will cause her to change her forecast. She consults a stock chart of Johnson & Johnson. In this example, we’ll assume there is some resistance developing around $64 in the short term. If this resistance level holds, the trade becomes less attractive. The at-expiration breakeven is $63.25, so the trade can still be a winner if Johnson & Johnson retreats. But Stacie is looking for the stock to approach $65. She will no longer like the risk/reward of this trade if it looks like that price rise won’t occur. She makes the decision that if Johnson & Johnson bounces off the $64 level over the next couple weeks, she will exit the position for fear that her outlook is wrong. If Johnson & Johnson drifts above $64, however, she will ride the trade out.
In this example, Stacie is willing to lose 1.00 per contract. Without taking into account theta or vega, that 1.00 loss in the option should occur at a stock price of about $63.28. Theta is somewhat relevant here. It helps Stacie’s potential for profit as time passes. As time passes and as the stock rises, so will theta, helping her even more. If the stock moves lower (against her) theta helps ease the pain somewhat, but the further in-the-money the put, the lower the theta.
Vega can be important here for two reasons: first, because of how implied volatility tends to change with market direction, and second, because it can be read as an indication o


k moves lower (against her) theta helps ease the pain somewhat, but the further in-the-money the put, the lower the theta.
Vega can be important here for two reasons: first, because of how implied volatility tends to change with market direction, and second, because it can be read as an indication of the market’s expectations.
The Double Whammy
With the stock around $64, there is a negative vega of about seven cents. As the stock moves lower, away from the strike, the vega gets a bit smaller. However, the market conditions that would lead to a decline in the price of Johnson & Johnson would likely cause implied volatility (IV) to rise. If the stock drops, Stacie would have two things working against her—delta and vega—a double whammy. Stacie needs to watch her vega.
Exhibit 5.6
shows the vega of Stacie’s put as it changes with time and direction.
EXHIBIT 5.6
Johnson & Johnson 65 put vega.
If after one week passes Johnson & Johnson gaps lower to, say, $63.00 a share, the vega will be 0.043 per contract. If IV subsequently rises 5 points as a result of the stock falling, vega will make Stacie’s puts theoretically worth 21.5 cents more per contract. She will lose $215 on vega (that’s 0.043 vega × 5 volatility points × 10 contracts) plus the adverse delta/gamma move.
A gap opening will cause her to miss the opportunity to stop herself out at her target price entirely. Even if the stock drifts lower, her targeted stop-loss price will likely come sooner than expected, as the option price will likely increase both by delta/gamma and vega resulting from rising volatility. This can cause her to have to cover sooner, which leaves less room for error. With this trade, increases in IV due to market direction can make it feel as if the delta is greater than it actually is as the market declines. Conversely, IV softening makes it feel as if the delta is smaller than it is as the market rises.
The second reason IV has importance for this trade (as for most other strategies) is that it can give some indication of how much the market thinks the stock can move. If IV is higher than normal, the market perceives there to be more risk than usual of future volatility. The question remains: Is the higher premium worth the risk?
The answer to this question is subjective. Part of the answer is based on Stacie’s assessment of future volatility. Is the market right? The other part is based on Stacie’s risk tolerance. Is she willing to endure the greater price swings associated with the potentially higher volatility? This can mean getting whipsawed, which is exiting a position after reaching a stop-loss point only to see the market reverse itself. The would-be profitable trade is closed for a loss. Higher volatility can also mean a higher likelihood of getting assigned and acquiring an unwanted long stock position.
Cash-Secured Puts
There are some situations where higher implied volatility may be a beneficial trade-off. What if Stacie’s motivation for shorting puts was different? What if she would like to own the stock, just not at the current market price? Stacie can sell ten 65 puts at 1.75 and deposit $63,250 in her trading account to secure the purchase of 1,000 shares of Johnson & Johnson if she gets assigned. The $63,250 is the $65 per share she will pay for the stock if she gets assigned, minus the 1.75 premium she received for the put × $100 × 10 contracts. Because the cash required to potentially purchase the stock is secured by cash sitting ready in the account, this is called a cash-secured put.
Her effective purchase price if assigned is $63.25—the same as her breakeven at expiration. The idea with this trade is that if Johnson & Johnson is anywhere under $65 per share at expiration, she will buy the stock effectively at $63.25. If assigned, the time premium of the put allows her to buy the stock at a discount compared with where it is priced when the trade is established, $64. The higher the time premium—or the higher the implied volatility—the bigger the discount.
This discount, however, is contingent on the stock not moving too much. If it is above $65 at expiration she won’t get assigned and therefore can only profit a maximum of 1.75 per contract. If the stock is below $63.25 at expiration, the time premium no longer represents a discount, in fact, the trade becomes a loser. In a way, Stacie is still selling volatility.
Covered Call
The problem with selling a naked call is that it has unlimited exposure to upside risk. Because of this, many traders simply avoid trading naked calls. A more common, and some would argue safer, method of selling calls is to sell them covered.
A covered call is when calls are sold and stock is purchased on a share-for-share basis to cover the unlimited upside risk of the call. For each call that is sold, 100 shares of the underlying security are bought. Because of the addition of stock to this strategy, covered calls are traded with a different motivation than naked calls.
There are clearl


urchased on a share-for-share basis to cover the unlimited upside risk of the call. For each call that is sold, 100 shares of the underlying security are bought. Because of the addition of stock to this strategy, covered calls are traded with a different motivation than naked calls.
There are clearly many similarities between these two strategies. The main goal for both is to harvest the premium of the call. The theta for the call is the same with or without the stock component. The gamma and vega for the two strategies are the same as well. The only difference is the stock. When stock is added to an option position, the net delta of the position is the only thing affected. Stock has a delta of one, and all its other greeks are zero.
The pivotal point for both positions is the strike price. That’s the point the trader wants the stock to be above or below at expiration. With the naked call, the maximum payout is reaped if the stock is below the strike at expiration, and there is unlimited risk above the strike. With the covered call, the maximum payout is reaped if the stock is above the strike at expiration. If the stock is below the strike at expiration, the risk is substantial—the stock can potentially go to zero.
Putting It on
There are a few important considerations with the covered call, both when putting on, or entering, the position and when taking off, or exiting, the trade. The risk/reward implications of implied volatility are important in the trade-planning process. Do I want to get paid more to assume more potential risk? More speculative traders like the higher premiums. More conservative (investment-oriented) covered-call sellers like the low implied risk of low-IV calls. Ultimately, a main focus of a covered call is the option premium. How fast can it go to zero without the movement hurting me? To determine this, the trader must study both theta and delta.
The first step in the process is determining which month and strike call to sell. In this example, Harley-Davidson Motor Company (HOG) is trading at about $69 per share. A trader, Bill, is neutral to slightly bullish on Harley-Davidson over the next three months.
Exhibit 5.7
shows a selection of available call options for Harley-Davidson with corresponding deltas and thetas.
EXHIBIT 5.7
Harley-Davidson calls.
In this example, the May 70 calls have 85 days until expiration and are 2.80 bid. If Harley-Davidson remained at $69 until May expiration, the 2.80 premium would represent a 4 percent profit over this 85-day period (2.80 ÷ 69). That’s an annualized return of about 17 percent ([0.04 / 85)] × 365).
Bill considers his alternatives. He can sell the April (57-day) 70 calls at 2.20 or the March (22-day) 70 calls at 0.85. Since there is a different number of days until expiration, Bill needs to compare the trades on an apples-to-apples basis. For this, he will look at theta and implied volatility.
Presumably, the March call has a theta advantage over the longer-term choices. The March 70 has a theta of 0.032, while the April 70’s theta is 0.026 and the May 70’s is 0.022. Based on his assessment of theta, Bill would have the inclination to sell the March. If he wants exposure for 90 days, when the March 70 call expires, he can roll into the April 70 call and then the May 70 call (more on this in subsequent chapters). This way Bill can continue to capitalize on the nonlinear rate of decay through May.
Next, Bill studies the IV term structure for the Harley-Davidson ATMs and finds the March has about a 19.2 percent IV, the April has a 23.3 percent IV, and the May has a 23 percent IV. March is the cheapest option by IV standards. This is not necessarily a favorable quality for a short candidate. Bill must weigh his assessment of all relevant information and then decide which trade is best. With this type of a strategy, the benefits of the higher theta can outweigh the disadvantages of selling the lower IV. In this case, Bill may actually like selling the lower IV. He may infer that the market believes Harley-Davidson will be less volatile during this period.
So far, Bill has been focusing his efforts on the 70 strike calls. If he trades the March 70 covered call, he will have a net delta of 0.588 per contract. That’s the negative 0.412 delta from shorting the call plus the 1.00 delta of the stock. His indifference point if the trade is held until expiration is $70.85. The indifference point is the point at which Bill would be indifferent as to whether he held only the stock or the covered call. This is figured by adding the strike price of $70 to the 0.85 premium. This is the effective sale price of the stock if the call is assigned. If Bill wants more potential for upside profit, he could sell a higher strike. He would have to sell the April or May 75, since the March 75s are a zero bid. This would give him a higher indifference point, and the upside profits would materialize quickly if HOG moved higher, since the covered-call deltas would be hi


potential for upside profit, he could sell a higher strike. He would have to sell the April or May 75, since the March 75s are a zero bid. This would give him a higher indifference point, and the upside profits would materialize quickly if HOG moved higher, since the covered-call deltas would be higher with the 75 calls. The April 75 covered-call net delta is 0.796 per contract (the stock delta of 1.00 minus the 0.204 delta of the call). The May 75 covered-call delta is 0.751.
But Bill is neutral to only slightly bullish. In this case, he’d rather have the higher premium—high theta is more desirable than high delta in this situation. Bill buys 1,000 shares of Harley-Davidson at $69 and sells 10 Harley-Davidson March 70 calls at 0.85.
Bill also needs to plan his exit. To exit, he must study two things: an at-expiration diagram and his greeks.
Exhibit 5.8
shows the P&(L) at expiration of the Harley-Davidson March 70 covered call.
Exhibit 5.9
shows the greeks.
EXHIBIT 5.8
Harley-Davidson covered call.
EXHIBIT 5.9
Greeks for Harley-Davidson covered call (per contract).
Delta
0.591
Gamma
−0.121
Theta
0.032
Vega
−0.066
Taking It Off
If the trade works out perfectly for Bill, 22 days from now Harley-Davidson will be trading right at $70. He’d profit on both delta and theta. If the trade isn’t exactly perfect, but still good, Harley-Davidson will be anywhere above $68.15 in 22 days. It’s the prospect that the trade may not be so good at March expiration that occupies Bill’s thoughts, but a trader has to hope for the best and plan for the worst.
If it starts to trend, Bill needs to react. The consequences to the stock’s trending to the upside are not quite so dire, although he might be somewhat frustrated with any lost opportunity above the indifference point. It’s the downside risk that Bill will more vehemently guard against.
First, the same IV/vega considerations exist as they did in the previous examples. In the event the trade is closed early, IV/vega may help or hinder profitability. A rise in implied volatility will likely accompany a decline in the stock price. This can bring Bill to his stop-loss sooner. Delta versus theta however, is the major consideration. He will plan his exit price in advance and cover when the planned exit price is reached.
There are more moving parts with the covered call than a naked option. If Bill wants to close the position early, he can leg out, meaning close only one leg of the trade (the call or the stock) at a time. If he legs out of the trade, he’s likely to close the call first. The motivation for exiting a trade early is to reduce risk. A naked call is hardly less risky than a covered call.
Another tactic Bill can use, and in this case will plan to use, is rolling the call. When the March 70s expire, if Harley-Davidson is still in the same range and his outlook is still the same, he will sell April calls to continue the position. After the April options expire, he’ll plan to sell the Mays.
With this in mind, Bill may consider rolling into the Aprils before March expiration. If it is close to expiration and Harley-Davidson is trading lower, theta and delta will both have devalued the calls. At the point when options are close to expiration and far enough OTM to be offered close to zero, say 0.05, the greeks and the pricing model become irrelevant. Bill must consider in absolute terms if it is worth waiting until expiration to make 0.05. If there is a lot of time until expiration, the answer is likely to be no. This is when Bill will be apt to roll into the Aprils. He’ll buy the March 70s for a nickel, a dime, or maybe 0.15 and at the same time sell the Aprils at the bid. This assumes he wants to continue to carry the position. If the roll is entered as a single order, it is called a calendar spread or a time spread.
Covered Put
The last position in the family of basic volatility-selling strategies is the covered put, sometimes referred to as selling puts and stock. In a covered put, a trader sells both puts and stock on a one-to-one basis. The term
covered put
is a bit of a misnomer, as the strategy changes from limited risk to unlimited risk when short stock is added to the short put. A naked put can produce only losses until the stock goes to zero—still a substantial loss. Adding short stock means that above the strike gains on the put are limited, while losses on the stock are unlimited. The covered put functions very much like a naked call. In fact, they are synthetically equal. This concept will be addressed further in the next chapter.
Let’s looks at another trader, Libby. Libby is an active trader who trades several positions at once. Libby believes the overall market is in a range and will continue as such over the next few weeks. She currently holds a short stock position of 1,000 shares in Harley-Davidson. She is becoming more neutral on the stock and would consider buying in her short if the market dipped. She may consider entering into a covered-put position. T


in a range and will continue as such over the next few weeks. She currently holds a short stock position of 1,000 shares in Harley-Davidson. She is becoming more neutral on the stock and would consider buying in her short if the market dipped. She may consider entering into a covered-put position. There is one caveat: Libby is leaving for a cruise in two weeks and does not want to carry any positions while she is away. She decides she will sell the covered put and actively manage the trade until her vacation. Libby will sell 10 Harley-Davidson March (22-day) 70 puts at 1.85 against her short 1,000 shares of Harley-Davidson, which is trading at $69 per share.
She knows that her maximum profit if the stock declines and assignment occurs will be $850. That’s 0.85 × $100 × 10 contracts. Win or lose, she will close the position in two weeks when there are only eight days until expiration. To trade this covered put she needs to watch her greeks.
Exhibit 5.10
shows the greeks for the Harley-Davidson 70-strike covered put.
EXHIBIT 5.10
Greeks for Harley-Davidson covered put (per contract).
Delta
−0.419
Gamma
−0.106
Theta
0.031
Vega
−0.066
Libby is really focusing on theta. It is currently about $0.03 per day but will increase if the put stays close-to-the-money. In two weeks, the time premium will have decayed significantly. A move downward will help, too, as the −0.419 delta indicates.
Exhibit 5.11
displays an array of theoretical values of the put at eight days until expiration as the stock price changes.
EXHIBIT 5.11
HOG 70 put values at 8 days to expiry.
As long as Harley-Davidson stays below the strike price, Libby can look at her put from a premium-over-parity standpoint. Below the strike, the intrinsic value of the put doesn’t matter too much, because losses on intrinsic value are offset by gains on the stock. For Libby, all that really matters is the time value. She sold the puts at 0.85 over parity. If Harley-Davidson is trading at $68 with eight days to go, she can buy her puts back for 0.12 over parity. That’s a 73-cent profit, or $730 on her 10 contracts. This doesn’t account for any changes in the time value that may occur as a result of vega, but vega will be small with Harley-Davidson at $68 and eight days to go. At this point, she would likely close down the whole position—buying the puts and buying the stock—to take a profit on a position that worked out just about exactly as planned.
Her risk, though, is to the upside. A big rally in the stock can cause big losses. From a theoretical standpoint, losses are potentially unlimited with this type of trade. If the stock is above the strike, she needs to have a mental stop order in mind and execute the closing order with discipline.
Curious Similarities
These basic volatility-selling strategies are fairly simple in nature. If the trader believes a stock will not rise above a certain price, the most straightforward way to trade the forecast is to sell a call. Likewise, if the trader believes the stock will not go below a certain price he can sell a put. The covered call and covered put are also ways to generate income on long or short stock positions that have these same price thresholds. In fact, the covered call and covered put have some curious similarities to the naked put and naked call. The similarities between the two pairs of positions are no coincidence. The following chapter sheds light on these similarities.


CHAPTER 6
Put-Call Parity and Synthetics
In order to understand more complex spread strategies involving two or more options, it is essential to understand the arbitrage relationship of the put-call pair. Puts and calls of the same month and strike on the same underlying have prices that are defined in a mathematical relationship. They also have distinctly related vegas, gammas, thetas, and deltas. This chapter will show how the metrics of these options are interrelated. It will also explore synthetics and the idea that by adding stock to a position, a trader may trade with indifference either a call or a put to the same effect.
Put-Call Parity Essentials
Before the creation of the Black-Scholes model, option pricing was hardly an exact science. Traders had only a few mathematical tools available to compare the relative prices of options. One such tool, put-call parity, stems from the fact that puts and calls on the same class sharing the same month and strike can have the same functionality when stock is introduced.
For example, traders wanting to own a stock with limited risk can buy a married put: long stock and a long put on a share-for-share basis. The traders have infinite profit potential, and the risk of the position is limited below the strike price of the option. Conceptually, long calls have the same risk/reward profile—unlimited profit potential and limited risk below the strike.
Exhibit 6.1
is an overview of the at-expiration diagrams of a married put and a long call.
EXHIBIT 6.1
Long call vs. long stock + long put (married put).
Married puts and long calls sharing the same month and strike on the same security have at-expiration diagrams with the same shape. They have the same volatility value and should trade around the same implied volatility (IV). Strategically, these two positions provide the same service to a trader, but depending on margin requirements, the married put may require more capital to establish, because the trader must buy not just the option but also the stock.
The stock component of the married put could be purchased on margin. Buying stock on margin is borrowing capital to finance a stock purchase. This means the trader has to pay interest on these borrowed funds. Even if the stock is purchased without borrowing, there is opportunity cost associated with the cash used to pay for the stock. The capital is tied up. If the trader wants to use funds to buy another asset, he will have to borrow money, which will incur an interest obligation. Furthermore, if the trader doesn’t invest capital in the stock, the capital will rest in an interest-bearing account. The trader forgoes that interest when he buys a stock. However the trader finances the purchase, there is an interest cost associated with the transaction.
Both of these positions, the long call and the married put, give a trader exposure to stock price advances above the strike price. The important difference between the two trades is the value of the stock below the strike price—the part of the trade that is not at risk in either the long call or the married put. On this portion of the invested capital, the trader pays interest with the married put (whether actually or in the form of opportunity cost). This interest component is a pricing consideration that adds cost to the married put and not the long call.
So if the married put is a more expensive endeavor than the long call because of the interest paid on the investment portion that is below the strike, why would anyone buy a married put? Wouldn’t traders instead buy the less expensive—less capital intensive—long call? Given the additional interest expense, they would rather buy the call. This relates to the concept of arbitrage. Given two effectively identical choices, rational traders will choose to buy the less expensive alternative. The market as a whole would buy the calls, creating demand which would cause upward price pressure on the call. The price of the call would rise until its interest advantage over the married put was gone. In a robust market with many savvy traders, arbitrage opportunities don’t exist for very long.
It is possible to mathematically state the equilibrium point toward which the market forces the prices of call and put options by use of the put-call parity. As shown in Chapter 2, the put-call parity states
where c is the call premium, PV(x) is the present value of the strike price, p is the put premium and s is the stock price.
Another, less academic and more trader-friendly way of stating this equation is
where Interest is calculated as
Interest = Strike × Interest Rate ×(Days to Expiration/365)
1
The two versions of the put-call parity stated here hold true for European options on non-dividend-paying stocks.
Dividends
Another difference between call and married-put values is dividends. A call option does not extend to its owner the right to receive a dividend payment. Traders, however, who are long a put and long stock are entitled to a di

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re hold true for European options on non-dividend-paying stocks.
Dividends
Another difference between call and married-put values is dividends. A call option does not extend to its owner the right to receive a dividend payment. Traders, however, who are long a put and long stock are entitled to a dividend if it is the corporation’s policy to distribute dividends to its shareholders.
An adjustment must be made to the put-call parity to account for the possibility of a dividend payment. The equation must be adjusted to account for the absence of dividends paid to call holders. For a dividend-paying stock, the put-call parity states
The interest advantage and dividend disadvantage of owning a call is removed from the market by arbitrageurs. Ultimately, that is what is expressed in the put-call parity. It’s a way to measure the point at which the arbitrage opportunity ceases to exist. When interest and dividends are factored in, a long call is an equal position to a long put paired with long stock. In options nomenclature, a long put with long stock is a synthetic long call. Algebraically rearranging the above equation:
The interest and dividend variables in this equation are often referred to as the basis. From this equation, other synthetic relationships can be algebraically derived, like the synthetic long put.
A synthetic long put is created by buying a call and selling (short) stock. The at-expiration diagrams in
Exhibit 6.2
show identical payouts for these two trades.
EXHIBIT 6.2
Long put vs. long call + short stock.
The concept of synthetics can become more approachable when studied from the perspective of delta as well. Take the 50-strike put and call listed on a $50 stock. A general rule of thumb in the put-call pair is that the call delta plus the put delta equals 1.00 when the signs are ignored. If the 50 put in this example has a −0.45 delta, the 50 call will have a 0.55 delta. By combining the long call (0.55 delta) with short stock (–1.00 delta), we get a synthetic long put with a −0.45 delta, just like the actual put. The directional risk is the same for the synthetic put and the actual put.
A synthetic short put can be created by selling a call of the same month and strike and buying stock on a share-for-share basis (i.e., a covered call). This is indicated mathematically by multiplying both sides of the put-call parity equation by −1:
The at-expiration diagrams, shown in
Exhibit 6.3
, are again conceptually the same.
EXHIBIT 6.3
Short put vs. short call + long stock.
A short (negative) put is equal to a short (negative) call plus long stock, after the basis adjustment. Consider that if the put is sold instead of buying stock and selling a call, the interest that would otherwise be paid on the cost of the stock up to the strike price is a savings to the put seller. To balance the equation, the interest benefit of the short put must be added to the call side (or subtracted from the put side). It is the same with dividends. The dividend benefit of owning the stock must be subtracted from the call side to make it equal to the short put side (or added to the put side to make it equal the call side).
The same delta concept applies here. The short 50-strike put in our example would have a 0.45 delta. The short call would have a −0.55 delta. Buying one hundred shares along with selling the call gives the synthetic short put a net delta of 0.45 (–0.55 + 1.00).
Similarly, a synthetic short call can be created by selling a put and selling (short) one hundred shares of stock.
Exhibit 6.4
shows a conceptual overview of these two positions at expiration.
EXHIBIT 6.4
Short call vs. short put + short stock.
Put-call parity can be manipulated as shown here to illustrate the composition of the synthetic short call.
Most professional traders earn a short stock rebate on the proceeds they receive when they short stock—an advantage to the short-put–short-stock side of the equation. Additionally, short-stock sellers must pay dividends on the shares they are short—a liability to the married-put seller. To make all things equal, one subtracts interest and adds dividends to the put side of the equation.
Comparing Synthetic Calls and Puts
The common thread among the synthetic positions explained above is that, for a put-call pair, long options have synthetic equivalents involving long options, and short options have synthetic equivalents involving short options. After accounting for the basis, the four basic synthetic option positions are:
Because a call or put position is interchangeable with its synthetic position, an efficient market will ensure that the implied volatility is closely related for both. For example, if a long call has an IV of 25 percent, the corresponding put should have an IV of about 25 percent, because the long put can easily be converted to a synthetic long call and vice versa. The greeks will be similar for synthetically identical positions, too. The long options and their synthetic equivalents w


g call has an IV of 25 percent, the corresponding put should have an IV of about 25 percent, because the long put can easily be converted to a synthetic long call and vice versa. The greeks will be similar for synthetically identical positions, too. The long options and their synthetic equivalents will have positive gamma and vega with negative theta. The short options and their synthetics will have negative gamma and vega with positive theta.
American-Exercise Options
Put-call parity was designed for European-style options. The early exercise possibility of American-style options gums up the works a bit. Because a call (put) and a synthetic call (put) are functionally the same, it is logical to assume that the implied volatility and the greeks for both will be exactly the same. This is not necessarily true with American-style options. However, put-call parity may still be useful with American options when the limitations of the equation are understood. With at-the-money American-exercise options, the differences in the greeks for a put-call pair are subtle.
Exhibit 6.5
is a comparison of the greeks for the 50-strike call and the 50-strike put with the underlying at $50 and 66 days until expiration.
EXHIBIT 6.5
Greeks for a 50-strike put-call pair on a $50 stock.
Call
Put
Delta
0.554
0.457
Gamma
0.075
0.078
Theta
0.020
0.013
Vega
0.084
0.084
The examples used earlier in this chapter in describing the deltas of synthetics were predicated on the rule of thumb that the absolute values of call and put deltas add up to 1.00. To be a bit more realistic, consider that because of American exercise, the absolute delta values of put-call pairs don’t always add up to 1.00. In fact,
Exhibit 6.5
shows that the call has closer to a 0.554 delta. The put struck at the same price then has a 0.457 delta. By selling 100 shares against the long call, we can create a combined-position delta (call delta plus stock delta) that is very close to the put’s delta. The delta of this synthetic put is −0.446 (0.554 − 1.00). The delta of a put will always be similar to the delta of its corresponding synthetic put. This is also true with call–synthetic-call deltas. This relationship mathematically is
This holds true whether the options are in-, at-, or out-of-the-money. For example, with a stock at $54, the 50-put would have a −0.205 delta and the call would have a 0.799 delta. Selling 100 shares against the call to create the synthetic put yields a net delta of −0.201.
If long or short stock is added to a call or put to create a synthetic, delta will be the only greek affected. With that in mind, note the other greeks displayed in
Exhibit 6.5
—especially theta. Proportionally, the biggest difference in the table is in theta. The disparity is due in part to interest. When the effects of the interest component outweigh the effects of the dividend, the time value of the call can be higher than the time value of the put. Because the call must lose more premium than the put by expiration, the theta of the call must be higher than the theta of the put.
American exercise can also cause the option prices in put-call parity to not add up. Deep in-the-money (ITM) puts can trade at parity while the corresponding call still has time value. The put-call equation can be unbalanced. The same applies to calls on dividend-paying stocks as the dividend date approaches. When the date is imminent, calls can trade close to parity while the puts still have time value. The role of dividends will be discussed further in Chapter 8.
Synthetic Stock
Not only can synthetic calls and puts be derived by manipulation of put-call parity, but synthetic positions for the other security in the equation—stock—can be derived, as well. By isolating stock on one side of the equation, the formula becomes
After accounting for interest and dividends, buying a call and selling a put of the same strike and time to expiration creates the equivalent of a long stock position. This is called a synthetic stock position, or a combo. After accounting for the basis, the equation looks conceptually like this:
This is easy to appreciate when put-call parity is written out as it is here. It begins to make even more sense when considering at-expiration diagrams and the greeks.
Exhibit 6.6
illustrates a long stock position compared with a long call combined with a short put position.
EXHIBIT 6.6
Long stock vs. long call + short put.
A quick glance at these two strategies demonstrates that they are the same, but think about why. Consider the synthetic stock position if both options are held until expiration. The long call gives the trader the right to buy the stock at the strike price. The short put gives the trader the obligation to buy the stock at the same strike price. It doesn’t matter what the strike price is. As long as the strike is the same for the call and the put, the trader will have a long position in the underlying at the shared strike at expiration when exercise or assignment occ


gives the trader the obligation to buy the stock at the same strike price. It doesn’t matter what the strike price is. As long as the strike is the same for the call and the put, the trader will have a long position in the underlying at the shared strike at expiration when exercise or assignment occurs.
The options in this example are 50-strike options. At expiration, the trader can exercise the call to buy the underlying at $50 if the stock is above the strike. If the underlying is below the strike at expiration, he’ll get assigned on the put and buy the stock at $50. If the stock is bought, whether by exercise or assignment, the
effective price
of the potential stock purchase, however, is not necessarily $50.
For example, if the trader bought one 50-strike call at 3.50 and sold one 50-strike put at 1.50, he will effectively purchase the underlying at $52 upon exercise or assignment. Why? The trader paid a net of $2 to get a long position in the stock synthetically (3.50 of call premium debited minus 1.50 of put premium credited). Whether the call or the put is ITM, the effective purchase price of the stock will always be the strike price plus or minus the cost of establishing the synthetic, in this case, $52.
The question that begs to be asked is: would the trader rather buy the stock or pay $2 to have the same market exposure as long stock? Arbitrageurs in the market (with the help of the put-call parity) ensure that neither position—long stock or synthetic long stock—is better than the other.
For example, assume a stock is trading at $51.54. With 71 days until expiration, 26.35 IV, a 5 percent interest rate, and no dividends, the 50-strike call is theoretically worth 3.50, and the 50-strike put is theoretically worth 1.50.
Exhibit 6.7
charts the synthetic stock versus the actual stock when there are 71 days until expiration.
EXHIBIT 6.7
Long stock and synthetic long stock with 71 days to expiration.
Looking at this exhibit, it appears that being long the actual stock outperforms being long the stock synthetically. If the stock is purchased at $51.54, it need only rise a penny higher to profit (in the theoretical world where traders do not pay commissions on transactions). If the synthetic is purchased for $2, the stock needs to rise $0.46 to break even—an apparent disadvantage. This figure, however, does not include interest.
The synthetic stock offers the same risk/reward as actually being long the stock. There is a benefit, from the perspective of interest, to paying only $2 for this exposure rather than $51.54. The interest benefit here is about $0.486. We can find this number by calculating the interest as we did earlier in the chapter. Interest, again, is computed as the strike price times the interest rate times the number of days to expiration divided by the number of days in a year. The formula is as follows:
Inputting the numbers from this example:
The $0.486 of interest is about equal to the $0.46 disparity between the diagrams of the stock and the synthetic stock with 71 days until expiration. The difference is due mainly to rounding and the early-exercise potential of the American put. In mathematical terms
The synthetic long stock is approximately equal to the long stock position when considering the effect of interest. The two lines in
Exhibit 6.7
—representing stock and synthetic stock—would converge with each passing day as the calculated interest decreases.
This equation works as well for a synthetic short stock position; reversing the signs reveals the synthetic for short stock.
Or, in this case,
Shorting stock at $51.54 is about equal to selling the 50 call and buying the 50 put for a $2 credit based on the interest of 0.486 computed on the 50 strike. Again, the $0.016 disparity between the calculated interest and the actual difference between the synthetic value and the stock price is a function of rounding and early exercise. More on this in the “Conversions and Reversals” section.
Synthetic Stock Strategies
Ultimately, when we roll up our sleeves and get down to the nitty-gritty, options trading is less about having another alternative for trading the direction of the underlying than it is about trading the greeks. Different strategies allow traders to exploit different facets of option pricing. Some strategies allow traders to trade volatility. Some focus mainly on theta. Many of the strategies discussed in this section present ways for a trader to distill risk down mostly to interest rate exposure.
Conversions and Reversals
When calls and puts are combined to create synthetic stock, the main differences are the interest rate and dividends. This is important because the risks associated with interest and dividends can be isolated, and ultimately traded, when synthetic stock is combined with the underlying. There are two ways to combine synthetic stock with its underlying security: a conversion and a reversal.
Conversion
A conversion is a three-legged position in which a trader is