The investment seeks to track the performance of the S&P MidCap 400 Index to provide long-term capital growth by investing in equity securities of medium capitalization-weighted domestic corporations. The fund invests, under normal circumstances, at least 80% of its assets (net assets plus the amount of any borrowings made for investment purposes) in the stocks in the index in proportion to their market capitalization weighting in the index. It may also invest in a combination of ETFs and cash to maintain correlation to its index, to assist with index rebalances, and to meet redemption or purchase requests.