The investment seeks to obtain a high level of current income, preserve its assets and maintain liquidity. The fund invests 99.5% or more of its total assets in: debt securities issued or guaranteed as to principal or interest by the U.S. government, or by U.S. government agencies or instrumentalities; repurchase agreements that are collateralized fully by cash items or U.S. Treasury and U.S. government securities; and cash. It invests only in U.S. dollar-denominated securities and in instruments with a remaining maturity of 397 calendar days or less at the time of investment.