Invesco BulletShares 2024 Corporate Bond ETF seeks to track the investment results (before fees and expenses) of the Nasdaq BulletShares USD Corporate Bond 2024 Index (the “underlying 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 corporate bonds with maturities or, in some cases, “effective maturities” in the year 2024 (collectively, “2024 Bonds”).