The investment seeks track the performance of an index of extended-duration zero-coupon U.S. Treasury securities. The fund employs an indexing investment approach designed to track the performance of the Barclays U.S. Treasury STRIPS 20-30 Year Equal Par Bond Index. All of the fund's investments will be selected through the sampling process, and at least 80% of the fund's assets will be invested in U.S. Treasury securities held in the index. It maintains a dollar-weighted average maturity consistent with that of the index, which generally ranges between 20 and 30 years. It is expected to have a duration that is greater than 20 years.