Strategy. The Fund invests, under normal circumstances, at least 80% of its investable assets in obligations the income from which is exempt from federal income tax, that is, municipal obligations. The term investable assets in this prospectus 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 permitted by this policy may include certain municipal bonds, the interest on which is subject to the federal alternative minimum tax (AMT). The Fund, under normal conditions, invests at least 70% of its investable assets in investment grade municipal debt obligations. … Show more… The Fund invests, under normal circumstances, at least 80% of its investable assets in obligations the income from which is exempt from federal income tax, that is, municipal obligations. The term investable assets in this prospectus 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 permitted by this policy may include certain municipal bonds, the interest on which is subject to the federal alternative minimum tax (AMT). 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 below Baa3 by Moody's and below BBB- by S&P, or comparably rated by another NRSRO, and are considered speculative. The Fund may invest in obligations the interest and/or principal payments on which are insured by the bond insurers or other parties. In seeking to achieve the Funds investment objective, the subadviser will purchase securities that it believes represent the best values based on yield, maturity, issue, potential for price appreciation, risk, quality characteristics and expectations regarding economic and political developments, including movements in interest rates and demand for municipal bonds. 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 six years or less. The Fund's weighted average portfolio duration, however, may be longer at any time or from time to time depending on market conditions. 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 investment factors such as expected total return, yield, spread and potential for price appreciation as well as credit quality, maturity and risk. Show less