The investment seeks to track the investment results of the Bloomberg Barclays U.S. Universal 10+ Year Index (the underlying index). The underlying index measures the performance of U.S. dollar-denominated taxable bonds that are rated either investment-grade or high yield with remaining maturities greater than ten years. The fund generally will invest at least 90% of its assets in the component securities of the underlying index and may invest up to 10% of its assets in certain futures, options and swap contracts, cash and cash equivalents, as well as in securities not included in the underlying index.