Under normal circumstances, the Fund invests at least 80 percent of its net assets (plus any borrowings for investment purposes) in municipal obligations, the interest on which is exempt from regular federal income tax. This policy is fundamental and may not be changed without shareholder approval. The Fund may invest without limit in obligations the income from which is subject to the federal alternative minimum tax. The Fund will primarily invest in high yield municipal obligations under normal market conditions. For this purpose, high yield municipal obligations are municipal obligations rated at the time of investment either Baa or lower by Moodys Investors Service, Inc. (Moodys), or BBB or lower by either S&P Global Ratings (S&P) or Fitch Ratings (Fitch) or, if unrated, determined by the investment adviser to be of comparable quality. High yield municipal obligations rated below investment grade are also known as junk bonds. The Fund may invest in securities in any rating category, including those in default. For purposes of rating restrictions, if securities are rated differently by two or more rating agencies, the lowest rating will be used for any Fund rating restrictions.