• Stock Strategies
  • How to Take Your Emotions Out of the Sell Decision

    by Jim Norris

    Facing criticism from a colleague over modifications he made in his economic analysis, the famous British economist John Maynard Keynes once said: “When the facts change, I change my mind. What do you do, sir?”

    Keynes’ question is a relevant one for investors. Unless you are a buy-and-hold-forever investor, you will frequently be faced with the challenge of changing your mind. A decision to buy a stock will eventually and inevitably be followed by a decision to sell the stock.

    And when you decide to sell, you are effectively changing your mind about the prospects of the investment. Unfortunately, however, changing one’s mind is easier said than done. This is particularly true in the world of investments where uncertainty reigns and emotions run high. That combination—uncertainty and emotions—often leads to poor judgment.

    In his book “Against the Gods: The Remarkable Story of Risk,” Peter L. Bernstein says that the evidence “reveals repeated patterns of irrationality, inconsistency, and incompetence in the ways human beings arrive at decisions and choices when faced with uncertainty.”

    In the academic world, the disciplines of psychology, economics and finance have converged to study this issue, thus creating the field of behavioral finance. Numerous behavioral biases have been identified that inhibit human beings from making wise financial decisions.

    When the decision involves changing one’s mind, the emotional biases tend to become even more severe. We perceive that if we make a decision to sell a stock, we will be declaring our previous buy decision to be either a success (selling at a profit) or a failure (selling at a loss). Studies in behavioral finance have shown that our strong desire for success and our even stronger fear of failure can play havoc with our rational perception of the situation.

    So it should come as no surprise that investors tend to have more trouble with the sell decision than they do with the buy decision.

    Over the years, I have heard many investors tell me that it is more difficult to know when to sell a stock than it is to know when to buy it.

    Well-intended bits of wisdom and rules-of-thumb serve only to confuse the matter:

    • Investors are told to “let your winners run,” but are also told that “no one ever went broke taking profits.”
    • Investors are told to “cut your losses early,” but are also told to “average in” by buying more stock as the price declines.

    Obviously there is no magic formula to eliminate the uncertainty we face when making sell decisions, but we can do something about the emotional entanglements.

    One way to approach the problem is to completely automate the sell decision. Most often, this automation is based on stock price movements alone—for instance, if a stock price declines by, say, 20% it is automatically sold.

    Unfortunately, in addition to removing the unwanted emotional entanglements, this approach entirely removes the human element from the decision. For those of us who believe that people make better judgments than computers or mathematical formulas, this approach seems quite extreme.

    Improving Judgment

    Rather than talk about ways of removing our human judgment, I would like to focus on ways of improving our human judgment in the sell decision.

    Investing is both an art and a science, and experienced investors learn to take special precautions to prevent emotions from unduly influencing decisions, particularly sell decisions.

    In my own firm, a set of principles and procedures helps us in this regard. It is not called a “sell discipline” because that term is overused in the industry and many perceive it to imply the mindless automation described above. Instead, it is called an “accountability system.” It doesn’t automate our decisions, but it minimizes emotional influences by holding the human decision-makers accountable to a set of rational criteria.

    Importantly, this approach can be applied by anyone. We, of course, have a style of investing that is unique to us. But this accountability system can be useful regardless of your particular investment style.

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    Thesis Statement

    The process of laying the groundwork for a better sell decision should start even before you buy a stock. In particular, before a stock can be purchased, a thesis statement should be developed that spells out in some detail the reasons you believe it will turn out to be a good investment.

    The idea here is that in order to know when to sell a stock, you have to know with a fair amount of specificity why you bought it in the first place.

    The more solid this initial foundation, the less you will be affected by the inevitable ebb and flow of the confusing and potentially overwhelming flood of information and opinions surrounding the stock.

    Here are some guidelines for developing your thesis statement:

    Put It in Writing
    The thesis statement must be in writing. This is imperative. Don’t trust your memory. Not only is human memory imperfect, but the confidence we place in our memory can sometimes be disproportionate to the level of its accuracy. In other words, as time passes, the accuracy of our memory fades, but our confidence in what we think we remember can remain high. This is a dangerous combination, and the only way to counter it is with a written record. There is much wisdom to the old saying that “a short pencil is better than a long memory.”

    The written thesis statement does not have to be terribly long. This is not a doctoral dissertation to prove your complete knowledge of all facts and figures related to the subject. Rather, this is a recording of the basic tenets supporting your belief that this stock will be a good investment. A few paragraphs can usually suffice. In fact, there is a benefit in keeping it short because it forces you to focus only on what is most important. If you can’t keep it short, it may be because you aren’t really sure what is important.

    When Peter Lynch was managing the Magellan Fund, he used to impose a three-minute rule on his analysts for this reason. If they couldn’t adequately explain the thesis for owning a stock in less than three minutes, they wouldn’t invest in it.

    Decide What Would Make You Sell Before You Buy
    The time of purchase is the very best time to establish sell criteria, and you should include this is your thesis statement. The reason is that the emotional distractions are at their lowest point. Your judgment is not influenced by feelings of success or regret because you have experienced neither.

    Of course, unless you are clairvoyant (in which case you don’t need a sell discipline anyway), it would be impractical to come up with an exhaustive list of every event that could possibly make you decide to sell the stock. Detail and precision is not the goal here. Rather, the idea is to think through several plausible scenarios, including positive developments (the price target at which you would sell, for example), as well as negative developments (the business loses a key competitive advantage, for example).

    Sell criteria should be the inverse of buy criteria. Any other reason for selling (or choosing not to sell) a stock would be inconsistent with your investment philosophy. So, for example, buying a stock because you like the company’s growth characteristics, but choosing to hold on to it in the face of slowing growth simply because it has become cheap, is an inconsistency.

    Another example of inconsistency would be a value investor who attempts to “ride the momentum” of stocks long after they have become overvalued. Decide which reasons convince you to buy a stock, invert that reasoning, and you have a pretty good set of sell criteria.

    Quantify Your Expectations
    If emotion is to be limited, objectivity is the goal. Objectivity requires quantities that can be measured, but we live in a subjective world and the “qualities” we look for in an investment are not always easily “quantifiable.” This quality vs. quantity conundrum can be difficult to deal with, but that shouldn’t stop you from trying. Some quantification is better than none.

    Think through the thesis. If it plays out as you expect, what measurable results should you expect to see? What will be the most important? It will not be the same for every company. Sales growth may be a key driver for a retailer, margin expansion may be more important for a manufacturer, asset quality may be key to an investment in a finance company, or working capital management may be crucial for a distributor. The goal is not uniformity across all companies in the portfolio, nor is the goal to identify an exhaustive list. Rather, the goal is to identify the measures most likely to reflect the success or failure of the thesis over time. In fact, part of the value of the exercise is the process of deciding which few variables are the most crucial. I suggest no more than three or four variables for each company.

    Don’t Go It Alone
    Studies have shown that, except in rare instances (such as highly complex projects requiring specialized expertise from multiple disciplines), a committee is generally not the best forum for optimizing decision-making. But neither is an individual operating autonomously. Rather, the best decision-maker is an individual who has wise counsel from well-informed advisers. The interaction with advisers plays a critical role in avoiding emotional entanglements. Advisers can be more objective because they do not bear the weight of the responsibility for the decision, thus their own personal success or failure does not hang in the balance.

    I have always found this concept to be quite useful. At my own firm, we meet regularly before decisions are made. We challenge one another and, most importantly, we hold one another accountable. Ultimately, the decision rests with the analyst making the recommendation, but the group input ensures that the analyst’s decision is based on rational rather than emotional grounds.

    For an individual investor, a group of friends or an investment club can provide the same benefits as a formal investment committee, but it is important to make the meetings at least a little bit challenging. When buying a stock, share with the group your thesis statement and your sell criteria, then ask them to hold you accountable to that criteria over time.

    Measure the Progress
    Every quarter (or however often new data becomes available), the company’s actual performance on the key variables should be compared to the expected levels. Discrepancies should be noted. Large or persistent discrepancies should be a cause for concern and should trigger a complete review of the thesis.

    Review the Thesis Regularly—If the Facts Change, Change Your Mind
    The thesis behind each stock you own should be reviewed whenever a company announces earnings or releases significant data—for example, at least quarterly. Again, the goal is not a comprehensive rundown of every detail about the quarter but, rather, a review of how the original thesis is progressing.

    Is the original thesis intact, or not?

    That is the key question. If the answer is yes, you should hold on to the stock. If the answer is no, then the facts have changed and John Maynard Keynes would suggest that it is time to change your mind.

    The important point about this whole process is that it has finally forced you to this question, and you are making your decision based on the key facts and not the confusing ebb and flow of information and opinions I referred to earlier.

    An Example

    Let me illustrate with an example from the C&B Mid Cap Value Fund, which I co-manage. Based upon my recommendation, we owned stock in Food Lion Corporation. This is a grocery chain that is well known in the Southeastern part of the country.

    My thesis rested heavily upon an analysis of the company’s competitive advantages. Within the Southeast region, their advantages were formidable: Their name brand recognition was excellent, their cost position was significantly lower than any other competitor, and they dominated the low-price end of the market.

    As long as these facts remained true, it was reasonable to believe that the company could continue to grow a bit faster than the industry by gaining market share.

    Same store sales comparisons and margins were chosen as key variables to be monitored, since growth and the maintenance of their low-cost position were deemed to be crucial to the thesis.

    One of the risks I highlighted at the time of purchase was related to the consolidation going on in the grocery retailing industry. Specifically, I feared that Food Lion might be tempted to make a large acquisition. But it seemed just as likely that Food Lion might be acquired by someone else. Furthermore, I received assurances directly from senior management that whatever acquisitions they made would be non-dilutive to shareholders. This, combined with the company’s track record of making only very small acquisitions convinced me to recommend purchase of the stock.

    Several months later, however, the company announced the very large deal to acquire Hannaford Brothers stores. Naturally, my response was to immediately review my investment thesis to see how it would be affected by this new data.

    I was not very happy to see that, contrary to management’s earlier assurances, the deal was indeed quite dilutive. Even more disturbing was the fact that the Hannaford Brothers franchise operated at the high-price end of the market – completely opposite from the Food Lion franchise. Furthermore, Hannaford Brothers was a Northeast franchise where Food Lion had very little infrastructure or competitive advantage.

    It was quite clear that Food Lion was moving away from its strength. Not only were earnings being diluted, but the company’s core competitive advantages were being diluted as well. The variables I had chosen to objectively monitor had, technically, not yet been affected. But my confidence that the company could continue to meet these expectations was greatly diminished.

    Not surprisingly, the stock price went down significantly on the news. As a value investor, my emotional response was typical—I did not want to sell at such low prices.

    Fortunately, I had a group of colleagues to whom I had to report, and I knew they would be asking the ultimate question of whether the original thesis was still intact. I knew the answer would be quite clear. All of the key reasons I had originally bought the stock had been completely undermined by the acquisition. The facts had changed. It was time to change my mind.

    Following our sell decision, Food Lion stock continued to drift downward for some time. About a year later, the company was acquired, but at a very depressed price that reflected the diminished strength of the business. Had I chosen to hold on to the stock in hopes of regaining my earlier loss, I would have been greatly disappointed.

    Although we took a loss at the time and I had to admit a mistake, the decision to sell was a good one because we were able to redeploy our clients’ assets into other stocks that provided much better appreciation potential. The accountability system played an important role because it ensured the decision was based on rational criteria and not upon my emotional reaction to the situation.

    Facing the Facts

    It is no sin to be human. Unless you are a die-hard quantitative investor, you must believe that at least some human judgment in the investment process is a good thing. But studies in behavioral finance demonstrate that human emotion can play havoc with our judgment. Pure, undisciplined human judgment will lead to poor sell decisions, but so will mindless, robotic decision rules. Optimization lies somewhere in between. The system I have outlined disciplines human judgment without removing it. There are probably other successful systems, but this one works for us and, importantly, it can work for just about anyone.

    Jim Norris is a partner at Cooke & Bieler, an investment advisory firm based in Philadelphia. Mr. Norris is co-manager of the C&B Mid Cap Value Fund (CBMDX), a no-load mutual fund. The firm maintains a Web site at www.cooke-bieler.com.


    Paul from PA posted over 6 years ago:

    Excellent article.

    Don't forget though...

    "Absence makes the heart grow fonder." and "Out of sight, out of mind."

    William from LA posted over 4 years ago:

    I am just beginning with AAII and find this article to provide insights that I hope to be typical of available material.

    Donald from IL posted over 4 years ago:

    Very timely article. Would like the same written about when to sell a fund.

    Harold from MA posted over 4 years ago:

    This is a well written article, but it doesn't resonate with me. Once a month, or whatever period is convenient, reassess each security in your portfolio with fresh eyes, as if you were considering buying it. Compare the ones with weakest prospects with the prospects of securities you like but don't own. If the latter is more favorable, sell your worst holding and buy the other.

    You should never be in love with your stocks. Buy or sell decisions are always based on their future prospects (and tax considerations).

    Michele from FL posted over 4 years ago:

    this is a great article just what i needed

    James from CO posted over 4 years ago:

    35 years of in-depth experience has proven to me that the most effective and disciplined sell strategy for all asset classes is one that is implemented at the time a security is purchased. Using a simple moving average of the securities price - i.e. 20-days (1-month) for short-term traders, 126-days (6-months) for moderate investors, and 200-days (10-months) as a fail-safe for all others, would protect the majority of investors from destructive losses.

    Richard from CO posted over 4 years ago:

    A significenat consternation is all of my investments are in Vanguard funds. Coming out of the racession I chose to invest in bond and balanced funds. I believe this was a good plan at the time 2009+. However My portfolio is out of balance. My target is 60% bonds, 30% stocks and 10% cash. My current allocation is 75% bonds,20% stocks and 5% cash. Because of being over weighted in bonds and under weighted in stocks, I feel I need to rebalance. It is easy to do this. Sell a large % of a bond fund and buy a High yield stock fund. The bond fund is GINM that has a consistant divident. But too low to pay my bills and the fund has too little capital appreciation this year to make up for the reduced yield). The talk on the street is to decrease the bond exposier because of the sensitivity to interest rate increases and rates can't go anywhere but up. The bond fund has a duration of 4 yrs and a risk factor of 2. The risk factor of the high yield stock fund is 4. The reasonable action is to increase the risk with the stock and sell the GNMA fund. Where is he flaw in this reasoning. Intutivly I am not confortable with the plan but don't know why. I believe this is an possable example of when to sell. Will you please comment on this story.
    Thanks, dickrpb@comcast.net

    Richard Abbott from FL posted over 3 years ago:

    I have kept my allocation at 113 minus my age in conservative balanced mutual funds, the rest in quality corporate and government bonds funds with about 15% in the money market. I have had this allocation for the past 15 years and have averaged 8% a year. I'm 83 and enjoying my retirement with enough money to do whatever my wife and I want to do. I re-balance my portfolio whenever my allocation is more than 8 to 10% out of balance. This keeps the emotion out of the decision.

    Jerome Hodge from California posted over 3 years ago:

    I enjoyed this article very much. The author is spot on and is offering sage advice.
    As a subscriber to Value Line, they act as my 'adviser', while providing the written support for why I would purchase/sell an equity.
    Lastly, I am in at least my 4th reading of Benjamin Graham's "The Intelligent Investor". This book has been, and continues to be, a tremendous resource of knowledge to draw upon.

    Indigo85 from VA posted over 3 years ago:

    Excellent article. For me, the gem is "Sell criteria should be the inverse of buy criteria." The trick, of course, is to document your buy criteria, which this article motivated me to do more rigorously.

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