The investment seeks to track the investment results of the Markit iBoxx® USD Liquid Investment Grade Index. The fund will invest at least 80% of its assets in the component securities of the underlying index, and it will invest at least 90% of its assets in fixed income securities of the types included in the underlying index that the advisor believes will help the fund track the underlying index. The underlying index is designed to provide a broad representation of the U.S. dollar-denominated liquid investment-grade corporate bond market.