The investment seeks to track the investment results (before fees and expenses) of the S&P MidCap 400® Revenue-Weighted Index. The fund generally will invest at least 90% of its total assets in the securities that comprise the index. The index is designed to measure the performance of positive revenue-producing constituent securities of the S&P MidCap 400 ® Index (the ?Parent index?). The Parent index is comprised of common stocks of approximately 400 mid-capitalization companies that generally represent the mid-cap universe of the U.S. equity market. The fund is non-diversified.