The investment seeks to track as closely as possible, before fees and expenses, the total return of the Bloomberg Barclays US 5-10 Year Corporate Bond Index. To pursue its goal, the fund generally invests in securities that are included in the index. The index measures the performance of U.S. investment grade, taxable corporate bonds with maturities greater than or equal to five years and less than ten years that have $300 million or more of outstanding face value. It is the fund's policy that under normal circumstances it will invest at least 90% of its net assets in securities included in the index.