The investment seeks investment results that correspond generally to the price and yield performance, before fees and expenses, of the Barclays U.S. GNMA Bond Index (the "underlying index"). The fund generally invests at least 90% of its assets in the securities of the underlying index and in investments that provide substantially similar exposure to the securities in the underlying index. The underlying index is a market capitalization-weighted index that measures the performance of mortgage-backed pass-through securities issued by the Government National Mortgage Association ("GNMA" or "Ginnie Mae"). The fund is non-diversified.