The investment seeks to track the investment results (before fees and expenses) of the KBW Nasdaq Premium Yield Equity REIT Index (the underlying index). The fund generally will invest at least 90% of its total assets in the securities that comprise the underlying index. The underlying index is a modified-dividend yield-weighted index of domestic equity real estate investment trusts (REITs) of small- and mid-capitalization, as determined by the index provider. The underlying index is designed to track the performance of small- and mid-capitalization equity REITs that have competitive dividend yields and are publicly-traded in the U.S.