Strategy. Under normal market conditions, the Fund invests at least 80% of its net assets (plus any borrowings for investment purposes) in municipal obligations with final maturities of between one and ten years, the interest on which is exempt from regular federal income tax (the 80% Policy). For the purposes of the Funds 80% Policy, final maturity is defined as (i) the stated final maturity of a callable bond; (ii) the pre-refunded date of an existing pre-refunded bond; (iii) the earliest put date of a put bond; or (iv) the monthly re-set date of a municipal floating-rate bond or obligation. For municipal obligations held by the Fund that become pre-refunded after the Fund purchases such obligation, the final maturity of such … Show more… Under normal market conditions, the Fund invests at least 80% of its net assets (plus any borrowings for investment purposes) in municipal obligations with final maturities of between one and ten years, the interest on which is exempt from regular federal income tax (the 80% Policy). For the purposes of the Funds 80% Policy, final maturity is defined as (i) the stated final maturity of a callable bond; (ii) the pre-refunded date of an existing pre-refunded bond; (iii) the earliest put date of a put bond; or (iv) the monthly re-set date of a municipal floating-rate bond or obligation. For municipal obligations held by the Fund that become pre-refunded after the Fund purchases such obligation, the final maturity of such obligation remains the stated maturity. All municipal obligations maturing within a calendar year will be defined as having the same final maturity. At least 90% of the Funds net assets normally is invested in municipal obligations rated at least investment grade at the time of investment (which are those rated Baa or higher by Moodys Investors Service, Inc. (Moodys), or BBB or higher by either S&P Global Ratings (S&P) or Fitch Ratings (Fitch)) or, if unrated, determined by the investment adviser or sub-adviser to be of at least investment grade quality. The balance of net assets may be invested in municipal obligations rated below investment grade and in unrated municipal obligations considered to be of comparable quality by the investment adviser or sub-adviser (junk bonds). For purposes of rating restrictions, if securities are rated differently by two or more rating agencies, the highest rating is used. The Fund will not invest in an obligation if the interest on that obligation is subject to the federal alternative minimum tax. With respect to 20% of its net assets, the Fund may invest in municipal obligations that are not exempt from regular federal income tax, direct obligations of the U.S. Treasury and/or obligations of U.S. Government agencies, instrumentalities and government-sponsored enterprises. The Fund invests primarily in general obligation or revenue bonds. In pursuing its investment objective, the Fund seeks to weight investment in obligations such that at least 5% and not more than 15% of its net assets are invested in obligations with a final maturity in a year within the one-to-ten year maturity range (the weighted investment strategy). The Fund does not have a specific target for its average portfolio duration. When a municipal obligation has a final maturity of less than one year, the Fund intends to sell that security or let it mature and reinvest the proceeds in obligations with longer maturities. With respect to the Funds weighted investment strategy, the Fund intends to invest at least 5% of its net assets in securities with a final maturity of 10 years within 90 days of the beginning of the calendar year. The Funds portfolio is laddered by investing in municipal obligations with different final maturities so that some obligations age out of the one-to-ten year maturity range during each year. The investment sub-advisers process for selecting obligations for purchase and sale emphasizes the creditworthiness of the issuer or other person obligated to repay the obligation and the relative value of the obligation in the market. In evaluating creditworthiness, the investment sub-adviser considers ratings assigned by rating agencies and generally performs additional credit and investment analysis. The portfolio managers may also trade securities to seek to minimize capital gains to shareholders. These considerations may be taken into account alongside other factors in the investment selection process. Show less