A capitalization weighted index composed of all of the Russell 3000 stocks that are not represented in the Standard & Poor's 500 Index. The index is designed to allow investors to access the broad market for small- and mid-cap stocks without overlapping with commonly held stocks found in the S&P 500. The Small Cap Completeness Index is recalculated annually to account for both changes in the S&P 500 membership and in the Russell 3000. The average market cap for a member of the index is slightly less than $1 billion. Taobiz explains Russell Small Cap Completeness Index The range of market caps in the Completeness Index is very large; there are member companies with market caps as low as $30 million and those who top $75 billion. This is because some very large companies have yet to be included in the S&P 500, even though their market caps make them eligible.