Under normal market conditions, the fund will invest at least 80% of its net assets (plus any borrowings for investment purposes) in a portfolio of debt securities issued or guaranteed by the U.S. government (including U.S. Treasury bonds, notes and bills), its agencies or government-sponsored entities. The fund's investments in government securities include publicly-issued U.S. Treasury securities and mortgage-related securities such as pass-through securities, collateralized mortgage obligations (CMOs) and commercial mortgage-backed securities (CMBS). It is non-diversified.