Strategy. The Fund seeks to achieve its investment objective by investing, under normal conditions, at least 80% of its investable assets in municipal bonds that pay interest which is exempt from regular federal personal income tax. The term investable assets refers to the Funds net assets plus any borrowings for investment purposes. The Funds investable assets will be less than its total assets to the extent that it has borrowed money for non-investment purposes, such as to meet anticipated redemptions. The Funds investments may include certain municipal bonds, the interest on which is subject to the federal alternative minimum tax (AMT). Although the Fund may invest in instruments of any duration or maturity, the Fund, under normal conditions, seeks to maintain … Show more… The Fund seeks to achieve its investment objective by investing, under normal conditions, at least 80% of its investable assets in municipal bonds that pay interest which is exempt from regular federal personal income tax. The term investable assets refers to the Funds net assets plus any borrowings for investment purposes. The Funds investable assets will be less than its total assets to the extent that it has borrowed money for non-investment purposes, such as to meet anticipated redemptions. The Funds investments may include certain municipal bonds, the interest on which is subject to the federal alternative minimum tax (AMT). Although the Fund may invest in instruments of any duration or maturity, the Fund, under normal conditions, seeks to maintain a weighted average portfolio duration of approximately four years or less. The Funds weighted average portfolio duration, however, may be longer at any time or from time to time depending on market conditions. Municipal bonds in which the Fund invests include obligations issued by U.S. states and their subdivisions, authorities, instrumentalities and corporations, as well as obligations issued by U.S. territories (such as Puerto Rico, the U.S. Virgin Islands and Guam) that pay interest that is exempt from regular federal personal income tax. The Fund, under normal conditions, invests at least 70% of its investable assets in investment grade municipal debt obligations. Investment grade municipal debt obligations are bonds rated Baa3 or higher by Moody's Investors Service, Inc. (Moody's), or BBB- or higher by S&P Global Ratings (S&P), or comparably rated by another nationally recognized statistical rating organization (NRSRO), and unrated debt obligations that the subadviser believes are comparable in quality. The Fund, under normal conditions, may also invest up to 30% of its investable assets in high yield municipal debt obligations or junk bonds. High yield or junk bonds are rated Ba1 or lower by Moodys or BB+ or lower by S&P, or comparably rated by another NRSRO, and unrated debt obligations that the subadviser believes are comparable in quality. Lower rated bonds tend to offer higher yields, but also offer greater risks, than higher-rated bonds. The Fund may invest in obligations the interest and/or principal payments on which are insured by the bond insurers or other parties. The Fund may invest without limit in securities that generate income subject to the AMT. The Fund generally emphasizes revenue bonds over general obligation bonds. General obligation bonds are obligations supported by the credit of an issuer that has the power to tax and are payable from that issuers general revenues and not from any specific source. Revenue bonds, on the other hand, are payable from revenues derived from a particular source or project. In managing the Funds assets, the subadviser uses a combination of top-down economic analysis and bottom-up research in conjunction with proprietary quantitative models and risk management systems. In the top-down economic analysis, the subadviser develops views on economic, policy and market trends. In its bottom-up research, the subadviser develops an internal rating and outlook on issuers. The rating and outlook are determined based on a thorough review of the financial health and trends of the issuer. The subadviser may also consider factors such as expected total return, yield, spread and potential for price appreciation as well as credit quality, maturity and risk. In determining which securities to buy and sell, the subadviser considers, among other things, fundamental research, yield, maturity, issue and expectations regarding economic and political developments, including movements in interest rates and demand for municipal bonds. The subadviser may trade securities based on its outlook on interest rates. The subadviser also seeks to take advantage of differentials in yields with respect to securities with similar credit ratings and maturities, but which vary according to the purpose for which they were issued, as well as securities issued for similar purposes with similar maturities, but which vary according to ratings. The Fund may use derivatives to manage its duration to hedge against losses, and to try to improve returns. Show less