Russell 3000 Index
Definition of 'Russell 3000 Index'
A market capitalization weighted equity index maintained by the Russell Investment Group that seeks to be a benchmark of the entire U.S. stock market. More specifically, this index encompasses the 3,000 largest U.S.-traded stocks, in which the underlying companies are all incorporated in the U.S.
Investopedia explains 'Russell 3000 Index'
Stocks within the Russell 3000 index are reconstituted once a year (typically around May or June). At this time, the underlying companies are reranked based on their market capitalizations for that year. Furthermore, if a member is somehow rendered ineligible for continued membership during the year (such as by going private, being acquired or going bankrupt), no replacement is named until the next scheduled reconstitution.
Of the 3,000 stocks in the index, there are two very popular sub indexes that are followed to track the progress of the market. The largest 1,000 stocks become the Russell 1000 index (large cap index) and the subsequent 2,000 are known as the Russell 2000 index (small-cap index).