Strategy. The Fund normally invests at least 80% of its total assets in fixed income securities that comprise the Long Index. The Long Index is comprised of publicly traded municipal bonds that cover the U.S. dollar denominated long-term tax-exempt bond market. This 80% investment policy is non-fundamental and may be changed without shareholder approval upon 60 days' prior written notice to shareholders. The Fund has adopted a fundamental investment policy to invest at least 80% of its assets in municipal securities. Such policy cannot be changed without a shareholder vote. For purposes of this policy, the term assets means net assets plus the amount of any borrowings for investment purposes. This percentage limitation applies at the time of the investment. The … Show more… The Fund normally invests at least 80% of its total assets in fixed income securities that comprise the Long Index. The Long Index is comprised of publicly traded municipal bonds that cover the U.S. dollar denominated long-term tax-exempt bond market. This 80% investment policy is non-fundamental and may be changed without shareholder approval upon 60 days' prior written notice to shareholders. The Fund has adopted a fundamental investment policy to invest at least 80% of its assets in municipal securities. Such policy cannot be changed without a shareholder vote. For purposes of this policy, the term assets means net assets plus the amount of any borrowings for investment purposes. This percentage limitation applies at the time of the investment. The Fund, using a passive or indexing investment approach, attempts to approximate the investment performance of the Long Index. Unlike many investment companies that try to beat the performance of a benchmark index, the Fund does not try to beat the Long Index and does not take temporary defensive positions that are inconsistent with its investment objective of seeking to replicate the Long Index. Because of the practical difficulties and expense of purchasing all of the securities in the Long Index, the Fund does not purchase all of the securities in the Long Index. Instead, the Adviser utilizes a sampling methodology in seeking to achieve the Funds objective. As such, the Fund may purchase a subset of the bonds in the Long Index in an effort to hold a portfolio of bonds with generally the same risk and return characteristics of the Long Index. The Long Index is rebalanced on the last calendar day of the month. The Fund may concentrate its investments in a particular industry or group of industries to the extent that the Long Index concentrates in an industry or group of industries. As of April 30, 2025, each of the healthcare, general obligation and special tax ( i.e. revenue bonds backed by a special tax) sectors represented a significant portion of the Fund. Show less