SIShort Interest
The percentage of a company's float that has been sold short — betting the price will decline. A measure of bearish sentiment.
Formula
Short Interest (%) = (Shares Sold Short / Float) × 100
How to Interpret
Under 5% is normal. 10-20% is elevated. Above 20% is heavily shorted. High short interest can lead to short squeezes (rapid price spikes when shorts are forced to cover). But it can also mean smart money sees trouble ahead.
Why It Matters
Short interest reveals what the bears think. It's a contrarian indicator — extremely high short interest can signal either genuine problems or an incoming short squeeze. GameStop (2021) was the famous example of the latter.
Example
If a company has 100M shares in the float and 15M are sold short, the short interest is 15%.