The Fund seeks to track the investment results of the ICE U.S. Treasury 10-20 Year Bond Index (the Underlying Index), which measures the performance of public obligations of the U.S. Treasury that have a remaining maturity of greater than or equal to ten years and less than twenty years. As of February 29, 2024, there were 42 issues in the Underlying Index. The Underlying Index consists of publicly-issued U.S. Treasury securities that have a remaining maturity of greater than or equal to ten years and less than twenty years and have dollar 300 million or more of outstanding face value, excluding amounts held by the Federal Reserve System. In addition, the securities in the Underlying Index must be fixed-rate and denominated in U.S. dollars. Excluded from the Underlying Index are inflation-linked securities, Treasury bills, cash management bills, any government agency debt issued with or without a government guarantee and zero-coupon issues that have been stripped from coupon-paying bonds. The Underlying Index is market value weighted, and the securities in the Underlying Index are updated on the last business day of each month.