| The investment seeks daily investment results, before fees and expenses, of 100% of the inverse (or opposite) of the performance of the NYSE 20 Year Plus Treasury Bond Index. The fund, under normal circumstances, creates short positions by investing at least 80% of its net assets in financial instruments that provide exposure to the index. It invests the remainder of its assets in short-term debt instruments that have terms-to-maturity of less than 397 days and exhibit high quality credit profiles, including U.S. government securities and repurchase agreements. The fund is non-diversified. |