ProShares Short 20+ Year Treasury (the Fund) seeks daily investment results and interest income earned on cash and financial instruments, which correspond to the inverse (opposite) of the daily performance of the Barclays Capital 20+ Year U.S. Treasury Index (the Index). The Fund seeks a return of -100% of the return of an index for a single day. The Barclays Capital 20+ Year U.S. Treasury Index includes all publicly issued, United States Treasury securities that have a remaining maturity greater than 20 years, are non-convertible, are denominated in United States dollars, are rated investment grade, are fixed rate, and have more than $250 million par outstanding. The Index is weighted by the relative market value of all securities meeting the Index criteria. Excluded from the Index are certain special issues, such as flower bonds, targeted investor notes (TINs), U.S. Treasury inflation protected securities (TIPs), state and local government series bonds (SLGs), and coupon issues.