The main U.S. index is the Russell 3000® Index, which is divided into several sub-indexes, including the well-known small-cap Russell 2000® Index. The list of stocks in the Russell 3000 is compiled by the Tacoma, Washington-based Russell Investment Group. Using a rules-based and transparent process, Russell forms its indexes by listing all companies in descending order by market capitalization adjusted for float, which is the actual number of shares available for trading. In the United States, the top 3,000 stocks (those of the 3,000 largest companies) make up the broad-market Russell 3000® Index.
Large-Cap Indexes
The Russell 1000 Index® tracks the progress of the large-cap segment of the Russell 3000® Index, representing approximately 92% of the total market capitalization of that index.
Mid-Cap Indexes
The Russell Mid-Cap Index tracks the progress of the bottom 800 stocks in the Russell 1000® Index, representing approximately 26% of the total market capitalization of that index.
Small-Cap Indexes
The Russell 2000 Index tracks the progress of the small-cap segment of the Russell 3000® Index, representing approximately 8% of the total market capitalization of that index.
