The investment seeks to provide a rate of return that exceeds the rate of inflation over a business cycle, with an emphasis on both income and capital appreciation. The fund typically invests at least 90% of total assets in U.S. Treasury securities and in repurchase agreements collateralized by such securities. It also invests in long term U.S. Treasury bonds, including U.S. Treasury Strips, and U.S. Treasury bills or notes. The fund's effective duration of the funds holdings ranges from less than a year to a maximum of 25 years.