The investment seeks to track the investment results of an index composed of mid-capitalization U.S. equities that exhibit growth characteristics. The fund generally invests at least 90% of its assets in securities of the underlying index and in depositary receipts representing securities of the underlying index. It seeks to track the investment results of the Russell Midcap Growth Index (the "underlying index"), which measures the performance of the mid-capitalization growth sector of the U.S. equity market.