How interested are investors in stocks and options?

Short interest can help assess a stock’s sentiment; open interest, an option’s volatility.

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Despite a few bumps in the road, investors have mostly been in a bullish mood throughout 2016. The Dow, S&P 500®, and NASDAQ reached all-time highs this summer, and the MSCI World Index is not far from its own record high. Among the reasons for the bullish sentiment are:

  • Stabilizing growth: Steadying trends in China and continued expansion in the U.S. have helped improve the overall outlook.
  • Central bank support: Outside the U.S., several central banks are doing a lot to help stimulate economic activity.
  • Dividend seekers: Low bond yields have helped push investors toward dividend-paying stocks. Indeed, income-oriented stock investors have been rewarded, as the S&P 500 set a quarterly record for the amount of overall dividends in the second quarter, and the third quarter is on track to break that record with what may be the first quarterly dividend payout to surpass $100 billion.1 Of course, this has not come without risk as many dividend-paying stocks are now at all-time-high valuation levels and may not have as much upside as they once did.

However, a variety of risks remain. Among them:

  • Slow growth: Despite the positive signs in the U.S. and China, the IMF forecasts global growth to be just 3.4% in 2017.
  • Profitability under pressure: U.S. corporate earnings, while exhibiting some signs of improvement, are on pace to decline for the fifth straight quarter.2
  • Rich valuations: Flows into index funds may have helped artificially push markets higher, regardless of whether the fundamentals justify such prices. Additionally, in the search for income, many investors have helped drive "bond proxies" like consumer staples, utility, and telecom stocks to very high valuations, which may or may not be supported by their fundamentals.
  • Expectations for a rate hike: As of September 6, fed funds futures point to a 51% probability of a rate hike by the Federal Reserve in December.

In such an environment, it is more important than ever do do your research and use all of the tools at your disposal. Doing your fundamental research is always the first key step, but when it comes to assessing market sentiment, you might also consider adding a few indicators to your investing toolkit. Here, we focus on two technical indicators: short interest for stocks and open interest for options.

What is short interest?

Short interest is the number of shares of a particular stock that have been sold short. An investor who is short will potentially profit if the price declines. Many investors think it is bearish for a stock to have high or rising short interest.

Short interest is commonly expressed as a percentage—the number of shares sold short divided by the total number of outstanding shares. Suppose there are 10 total outstanding shares of a hypothetical stock. If one of those shares is sold short, the short interest as a percentage of outstanding shares will be 10% (1 ÷ 10 = 10%).

If a relatively large percentage of short interest exists relative to similar stocks or to the stock’s own historical levels, it may indicate that sentiment is generally pessimistic for the stock. For example, if stock A has short interest of 20% and stock B has short interest of 5%, based only on this indicator, stock A may be considered more bearish by investors.

The stock screener can help you find stocks with high short interest. Below is a list of 10 large-cap stocks with the most short interest as a percentage of outstanding shares, as of September 1, 2016.

Large-cap stocks with relatively high short interest
Symbol Company name Market capitalization Short interest as % of shares outstanding
DE DEERE AND CO $26.0B 10.13%
MYL MYLAN NV $23.7B 10.12%
Source: Fidelity Investments, as of September 1, 2016.

Why you might care about short interest

As with most technical indicators, this tool is not meant to be used in isolation. Rather, investors can use short interest to quickly compare sentiment between stocks. For instance, if a stock has a relatively high amount of short interest, it may suggest that there is a pessimistic outlook warranting further investigation. If a stock has a relatively low amount of short interest, it could indicate that the stock is generally well perceived by the investor community, which may be an additional reason to be positive about the stock.

Of course, the amount of short interest does not necessarily impact how a stock will perform.

Moreover, short interest can be a double-edged sword. Consider the so-called short squeeze, which occurs when the price of a stock with a relatively high amount of short interest increases at an unexpectedly fast pace. If the stock is consistently moving higher, and short sellers no longer believe it will decline in price, they may decide to cut their losses and close out their short positions by purchasing the stock. This action can result in temporarily “squeezing” the price higher. If you have a short position (which is a risky strategy in and of itself), the potential for a short squeeze is an even bigger risk to consider.

Many traders will also look at days to cover to evaluate a stock’s short interest. Days to cover is short interest divided by average daily volume. This can be important because it attempts to measure how long it may take to close out short positions and, consequently, the potential impact of a short squeeze. You can find days to cover on by selecting “Compare” on a stock’s snapshot page.

In sum, short interest can serve as another piece of information to assess a potential investment. You should not invest based solely on short interest; however, you can use it to help assess sentiment for a particular investment.

What is open interest?

For options investors, a useful tool to estimate volatility is open interest, which is the total number of options contracts that have not been exercised, closed out, or expired. This differs from volume in that open interest increases when a position is initiated and it decreases when the position is closed out; whereas volume will increase in both instances.

For example, suppose you bought a call option on the S&P 500 Index. This contract is now “open” and, consequently, open interest will increase. If you were to exercise that option one week from today, the contract would then be closed and open interest would decrease.

Meanwhile, volume would increase when you purchased the option and when you sold the option. Thus, you might think of open interest as a measure of active and open positions, and volume as reflecting total trading activity.

The options screener can help you identify options with a certain level of open interest, including those in the Market Scanner provided by LiveVol, a third-party independent research company. This screen attempts to identify options with underlying securities that have open interest at least 300% above their historical average.

For example, here is a list of the top ten stocks whose options have the highest open interest that is at least 300% above their historical average, as of September 1, 2016:

  • G&K Services (GK)
  • Quorum Health (QHC)
  • The GEO Group (GEO)
  • West Marine (WMAR)
  • Bottomline Technologies (EPAY)
  • State Auto Financial (STFC)
  • Corrections Corp of America (CXW)
  • Trinseo (TSE)
  • Liberty Interactive Group (QVCA)
  • Hain Celestial Group (HAIN)

Why you might care about open interest

Open interest is particularly important for options traders, as it can help measure the potential future liquidity for a particular contract, as well as the potential volatility in the underlying asset. High open interest (and high volume) is a sign of strong liquidity—which is beneficial to investors. Low open interest (and low volume) may be a sign of weak liquidity.

High open interest can also indicate the potential for volatility. If open interest were to suddenly spike, for instance, it might indicate investors’ belief in the potential for a short-term increase in the underlying stock’s volatility. The reason is that an increased amount of shares controlled by open options contracts might result in future price moves in the underlying stock—if the options are exercised.

Note that a sudden increase, or decrease, in open interest does not necessarily suggest which direction the stock might move. Rather, it may simply indicate there could be a change in the level of volatility. A change in the level of volatility could impact your decision to use different option-related strategies, such as choosing to establish long straddles and strangles for periods of expected high volatility, or butterflys and iron condors for periods of expected low volatility.

Still, some technical analysts think increasing open interest can be used to confirm an increase or decrease in the price of a stock or index. A rise in open interest coinciding with a rise in the price of a stock or index might be due to an increase in long positions (e.g., call options). This could be viewed by some as a bullish signal. Alternatively, if the price is moving higher or lower, but is not confirmed by an increase in open interest as well, that divergence could potentially be a signal that the bullish or bearish momentum may not continue.

To evaluate open interest, you can compare a current level of open interest to previous levels, or you might assess current open interest relative to the volume of contracts traded.

Investing implications

As with all investing endeavors, knowledge and information are essential. Knowing what these indicators are and how they can help you evaluate your investments may help improve your outcomes.

Learn more

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Options trading entails significant risk and is not appropriate for all investors. Certain complex options strategies carry additional risk. Before trading options, please read Characteristics and Risks of Standardized Options, and call 800-343-3548 to be approved for options trading. Supporting documentation for any claims, if applicable, will be furnished upon request.
1. Source: S&P Capital IQ, as of September 1, 2016.
2. Source: FactSet financial data and analytics, as of September 1, 2016.
Technical analysis focuses on market action—specifically, volume and price. Technical analysis is only one approach to analyzing stocks. When considering which stocks to buy or sell, you should use the approach that you’re most comfortable with. As with all your investments, you must make your own determination as to whether an investment in any particular security or securities is right for you based on your investment objectives, risk tolerance, and financial situation.
There are additional costs associated with option strategies that call for multiple purchases and sales of options, such as spreads, straddles, and collars, as compared with a single option trade.
Stock markets are volatile and can fluctuate significantly in response to company, industry, political, regulatory, market, or economic developments. Investing in stock involves risks, including the loss of principal.
Past performance is no guarantee of future results.
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