This fund aims to generate the highest possible current income, exempt from U.S. federal income tax, while simultaneously safeguarding invested capital. To achieve this, it typically allocates at least 80% of its net assets (including any borrowed funds for investment) to municipal bonds that produce income free from federal taxation. The portfolio primarily consists of investment-grade municipal and taxable bonds, meaning they are rated Baa3/BBB- or higher at the time of purchase, or are considered of comparable quality by the sub-adviser if unrated. Generally, the average effective duration of the fund's holdings ranges from three to eight years, although it maintains the flexibility to invest in individual bonds of any maturity or duration. Duration serves as an indicator of an investment's "interest rate risk," measuring how sensitive a bond or the overall portfolio is to shifts in interest rates; a longer duration typically signals greater sensitivity to rate changes and, consequently, higher long-term risk and return potential. As a liquid Exchange Traded Fund (ETF), investors can conveniently buy or sell shares throughout market trading hours.