The disposition effect

In short

I once watched a neighbor hold a losing stock for nine years, just so he would never have to say the loss out loud. You may know the feeling. The disposition effect is the habit of selling winning investments too soon and holding losing ones too long. It is common, and it is human, and it says nothing bad about your intelligence. When you look at a sale, it helps to ask what you would do if you had never owned the thing at all. It also helps to write down your reason for any sale and read it back the next morning. Taxes and trading costs are real, while the sting of admitting a mistake is only a feeling.

The whole of it

What it is

A friend of mine sold a stock the week it gained ten percent, and he told everyone at church about it. The same friend held another stock that had fallen by half, and he told nobody. Sound familiar? Two researchers named Hersh Shefrin and Meir Statman gave this pattern its name in a 1985 paper in The Journal of Finance. They called it the disposition effect, and the name has stuck ever since.

The pattern is simple to say. People like to lock in a gain, because a gain feels like a prize. People hate to lock in a loss, because a loss feels like a confession. So the winners go out the door early, and the losers stay on the porch and gather dust.

Nothing about this makes you foolish. It comes from how all of us feel about money. Daniel Kahneman and Amos Tversky described part of that feeling in their 1979 paper on prospect theory, published in Econometrica. Their point was that a loss stings more than an equal gain pleases. That is a very human thing.

How it works

If you are holding an investment that has dropped, you have probably told yourself a small story. It can sound like this: the price has to get back to what I paid before it feels settled. That price becomes a finish line in your mind. The market has no idea what you paid. It does not care. The price you paid is history, and what the thing is worth from here forward is a separate question.

Gains work the other way around. You see a nice profit and you feel a little rush of pride. Then a small voice says, take it before it disappears. So a sale happens, and then the investment keeps climbing, and you feel a bit foolish. That feeling teaches you to hurry next time.

Here is the odd part. The pull toward selling winners and keeping losers can cost you money in a plain, countable way. In the United States, the tax bill on a sale depends on whether you have a gain or a loss. Gains are taxed. Losses can offset gains. So the urge to sell winners early can bring the tax bill forward, while the urge to hold losers can leave a loss unused. That is the IRS rule on capital gains and losses, and you can read it yourself in IRS Publication 550, Investment Income and Expenses.

Keep one caution in mind. A tax rule is a reason to understand how things work. It is not a reason for any one choice. Your own situation shapes that, and a tax professional can look at it with you.

The numbers, and where to find yours

You do not need fancy tools to spot this habit in yourself. You need your account statements and an honest hour. Most brokerage websites show a report of realized gains and losses. That report lists what was sold and what was made or lost on each sale. Your year end tax form from your broker, called Form 1099 B, shows the same sales in the format the IRS expects.

Look at two things. First, how long you held each winner before it was sold. Second, how long you held each loser. If the winners left quickly and the losers lingered, you have met the disposition effect in your own life. No shame in that. I have met it in mine.

The tax side has its own numbers. The tax rate on long term gains depends on your income and on how long you held the asset, and the IRS sets the brackets. The amount of net loss you may deduct against ordinary income in one year is also set by law. Both figures can change, so check them on the IRS page for capital gains and losses. The current limit on the yearly loss deduction is the current figure, which the official source publishes each year, and the long term gain rate that applies to a middle income filer is the current figure, which the official source publishes each year.

A worked example

I want to tell you about a woman named Marcy. She is a nurse, careful with money, and she owns two investments in a regular taxable account. She bought Fund A for 5,000 dollars, and it is now worth 6,000 dollars. She bought Fund B for 5,000 dollars, and it is now worth 3,500 dollars.

Marcy feels good about Fund A and bad about Fund B. Her gut says to sell A and lock in the win, and to hold B until it comes back. Let us check what each path would mean, using plain figures.

Selling Fund A produces a gain. The math is 6,000 minus 5,000, which equals 1,000 dollars of gain. Selling Fund B produces a loss. The math is 3,500 minus 5,000, which equals negative 1,500 dollars, a loss of 1,500 dollars.

Now suppose Marcy sold both in the same year. Her gain of 1,000 and her loss of 1,500 would net out. The math is 1,000 minus 1,500, which equals negative 500 dollars. She would owe no tax on the gain, and she would have a 500 dollar net loss to run through the tax rules for deducting losses.

Now suppose she sold only Fund A. She would owe tax on the full 1,000 dollar gain. At an example rate of 15 percent, the tax would be 1,000 times 0.15, which equals 150 dollars. That rate is only for this example. Her real rate depends on her income and her holding period.

Notice what happened. Her gut pointed toward the path that created a tax bill. The other path used a loss to soften it. What fits Marcy depends on her goals, her timeline, and the funds themselves, and none of that shows up in the arithmetic above. The example shows only that the feeling and the numbers can point in different directions. A tax professional could look at her whole picture with her.

Where it goes wrong

I once knew a man who swore he would never sell at a loss. He held on through years of bad news, and the money sat frozen while other chances went by. Waiting has a price too. Money stuck in a losing position cannot be used for anything else.

The habit can also be fought too hard. Some folks, having read about this bias, decide that every loser must go on sight. That is not the cure either. The lesson is not about doing more or doing less. The lesson is to have good reasons for a sale and to name those reasons.

Watch out for the finish line trap. Waiting for a price to return to what you paid is a story you tell yourself. It ties a decision about the future to a number from the past.

Watch out for the wash sale rule, too. If you sell an investment at a loss and buy the same or a very similar one within thirty days before or after, the IRS may not let you claim the loss. IRS Publication 550 explains this rule in detail. It is worth reading before you act on any loss.

Trading costs matter as well. Every sale can carry a fee or a spread, and tax bills can eat into results. Frequent trading in the name of avoiding a bias can bring its own bill.

Questions to answer before you leave this page

If you had no memory of what you paid, would you still choose to own what you are holding today? Which of your investments do you avoid looking at, and why does that one bother you so much? Have you ever sold a winner early and felt relief, and did the relief come from good judgment or from the wish to feel finished? When did you last write down a reason for a sale before you made it? What would your account look like if you judged every holding by its future and not by your purchase price? And what small step, like a written note or a call to a tax professional, could you take this week to make your next decision a calmer one?