Average Volume

Average Volume is the mean number of shares traded per day over a specified period, usually 20, 50, or 200 days. It's a key metric for assessing liquidity and whether a stock is easy to buy or sell quickly.

Formula

Average Volume (20-day) = Total Volume Over Last 20 Days ÷ 20

Similarly, 50-day and 200-day averages divide total volume by 50 and 200, respectively.

Example

Tesla (TSLA) has an average daily volume around 120-150 million shares, making it highly liquid. An investor wanting to buy or sell a million shares of TSLA can do so easily without moving the price much. In contrast, a micro-cap stock might have average volume of only 100,000 shares daily, making it hard to buy or sell large positions.

How to Interpret It

• High average volume: The stock is liquid. You can buy or sell large positions without significantly moving the price.
• Low average volume: The stock is illiquid. Buying or selling a large position may cause slippage (paying more to buy or receiving less to sell).
• Increasing average volume: Suggests growing investor interest and improving liquidity.
• Decreasing average volume: Suggests waning interest and potentially deteriorating liquidity.
• Volume spikes above average: Something notable happened (earnings, news). This volume is higher than typical.
• Comparison: Use average volume to compare a stock's typical trading activity. A million-share day is normal for AAPL but exceptional for a penny stock.

Limitations

• Average volume can be misleading if volume trends have shifted (was high 20 days ago but is low now).
• Average volume includes all trading venues (exchanges, dark pools). Not all volume may be visible.
• A stock can have high average volume but low volume on a specific day you want to trade.
• Average volume doesn't indicate price direction, only how easy it is to trade.

Related Terms

• Volume — shares traded on a specific day
• Liquidity — how easily you can buy or sell without moving the price
• Bid-Ask Spread — the cost of liquidity
• Slippage — the difference between expected and actual prices when trading