The investment seeks daily investment results that correspond to the inverse (-1x) of the daily performance of the S&P SmallCap 600®. The fund invests in derivatives that ProShare Advisors believes, in combination, should have similar daily return characteristics as the inverse (-1x) of the daily return of the index. The index is a measure of small-cap company U.S. stock market performance. It is a float-adjusted, market capitalization-weighted index of 600 U.S. operating companies selected through a process that factors in criteria such as liquidity, price, market capitalization, financial viability and public float. The fund is non-diversified.