The investment seeks to track the performance of a benchmark index that measures the investment return of small- and mid-capitalization stocks. The fund employs an indexing investment approach designed to track the performance of the Standard & Poor's Completion Index, a broadly diversified index of stocks of small and mid-size U.S. companies. It invests all, or substantially all, of its assets in stocks of its target index, with nearly 80% of its assets invested in approximately 1,200 of the stocks in its target index, and the rest of its assets in a representative sample of the remaining stocks.