To pursue its goal, the fund normally invests at least 80% of its net assets, plus any borrowings for investment purposes, in bonds that are included in the Bloomberg U.S. Aggregate Bond Index (or other instruments with similar economic characteristics). The Bloomberg U.S. Aggregate Bond Index is a broad-based, unmanaged index that covers the U.S. dollar-denominated, investment grade (Baa/BBB or higher), fixed-rate, taxable bond market.