The investment seeks to track the investment results (before fees and expenses) of the Invesco BulletShares® Municipal Bond 2028 Index. The fund generally will invest at least 80% of its total assets in securities that comprise the underlying index. The underlying index seeks to measure the performance of a portfolio of U.S. dollar-denominated investment-grade municipal bonds with maturities or, in some cases, ?effective maturities,? in the year 2028 (collectively, ?2028 Bonds?). It is non-diversified.