What is Float? (Plain English Definition)
Definition: Float is the number of shares of a stock that are available for public trading, excluding shares held by insiders, executives, and other restricted holders.
Float Explained Simply
Float refers to the number of a company's shares that are freely available for the public to buy and sell on the stock exchange. It is calculated by taking the total shares outstanding and subtracting restricted shares held by company insiders, executives, and institutional holders who are subject to trading restrictions.
A company might have 1 billion total shares outstanding but a float of only 800 million if insiders and restricted holders own 200 million shares. The float is important because it determines the actual supply of shares available for trading. A smaller float means less supply, which can lead to larger price movements when demand changes.
For ETFs, float is relevant because many cap-weighted indices use float-adjusted market capitalization rather than total market cap. This means they weight companies based on the value of their publicly tradable shares rather than all shares. This approach better reflects the investable opportunity for ETF providers and prevents the index from being distorted by large blocks of illiquid insider holdings.
Float Example
Company X has 2 billion total shares outstanding at $50 per share, giving it a total market cap of $100 billion. But the founder still holds 400 million shares (20%) that cannot be freely traded. The float is 1.6 billion shares, with a float-adjusted market cap of $80 billion. An S&P 500 ETF would weight Company X based on the $80 billion float-adjusted cap rather than the $100 billion total cap.
Why Float Matters for ETF Investors
Understanding float helps ETF investors appreciate how indices are constructed and why some companies have a different weight in an index than you might expect based on total market cap. Float adjustment prevents ETFs from overweighting companies where most shares are locked up by insiders. For ETF investors, float also affects individual stock liquidity within an ETF. Companies with small floats relative to their market cap can experience sharper price swings, which may increase volatility in ETFs that hold them. This is generally more of a concern for small-cap and emerging market ETFs where insider ownership tends to be higher.
Float vs Market Capitalization
| Float | Market Capitalization |
|---|---|
| Float is the number of shares of a stock that are available for public trading, excluding shares held by insiders, executives, and other restricted holders. | See full definition of Market Capitalization |
While float and market capitalization are related concepts, they serve different purposes in the world of ETF investing. Understanding both terms helps you make more informed decisions about which funds to include in your portfolio and how to evaluate their performance.
Related Terms
Deepen your understanding of ETF investing by exploring these related concepts:
Market Capitalization
Market capitalization is the total value of a company's outstanding shares, calculated by multiplying the stock price by the number of shares.
Capitalization-Weighted Index
A capitalization-weighted index assigns more weight to companies with larger market values, so bigger companies have more influence on the index's performance.
Trading Volume
Trading volume is the total number of shares of a security that are bought and sold during a specific time period, usually one day.
Liquidity
Liquidity refers to how quickly and easily an investment can be bought or sold without significantly affecting its price.
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