Strategy. In seeking to achieve its objective, the fund may accept risks to capital value deemed prudent by the fund's investment adviser to take advantage of opportunities for higher current income on municipal bonds. Municipal bonds are debt obligations that pay interest that is exempt from federal taxation, with payments made from a wide variety of sources, including governmental revenue streams and private enterprises. Under normal circumstances, the fund will invest at least 80% of its assets in, or derive at least 80% of its income from, securities that are exempt from regular federal income tax. The fund may invest, without limitation, in private activity bonds whose interest is generally subject to the federal alternative minimum tax. The fund invests at … Show more… In seeking to achieve its objective, the fund may accept risks to capital value deemed prudent by the fund's investment adviser to take advantage of opportunities for higher current income on municipal bonds. Municipal bonds are debt obligations that pay interest that is exempt from federal taxation, with payments made from a wide variety of sources, including governmental revenue streams and private enterprises. Under normal circumstances, the fund will invest at least 80% of its assets in, or derive at least 80% of its income from, securities that are exempt from regular federal income tax. The fund may invest, without limitation, in private activity bonds whose interest is generally subject to the federal alternative minimum tax. The fund invests at least 60% of its portfolio in debt securities rated BBB+ or below or Baa1 or below by Nationally Recognized Statistical Rating Organizations designated by the funds investment adviser, or unrated but determined by the funds investment adviser to be of equivalent quality. Securities rated BB+ or below or Ba1 or below are sometimes referred to as junk bonds. The funds assets are managed by a team of portfolio managers. Under this approach, the funds managers work together to oversee the funds entire portfolio. For more information regarding the investment process of the fund, see the Management and organization section of this prospectus. The fund relies on the professional judgment of its investment adviser to make decisions about the funds portfolio investments. The basic investment philosophy of the investment adviser is to seek to invest in attractively priced securities that, in its opinion, represent good investment opportunities. Securities may be sold when the investment adviser believes that they no longer represent relatively attractive investment opportunities. Show less