The iShares Russell 1000 ETF (Ticker: IWB) seeks investment results that, before fees and expenses, correspond generally to the performance of the Russell 1000 Index. The index is composed of the largest 1000 companies in the Russell 3000. Total market capitalization is determined by combining total outstanding shares times the market price as of May 31 for those eligible at annual reconstitution on the last Friday in June. Initial public offerings (IPOs) may be added quarterly. Deletions due to mergers and acquisitions are not replaced until the next reconstruction in June.