The aim is for the investment to reflect the performance of the S&P 500 Inverse Daily Index (Index) which provides the opposite performance of the S&P 500 Total Return (TR) Index (Underlying Index) on a daily basis plus a rate of interest. This means that the level of the Index should rise when the Underlying Index falls and fall when the Underlying Index rises on a daily basis. The interest rate added to the Index level is based on double the rate at which banks in London lend US dollars to each other overnight earned on the short position. The Underlying Index is designed to reflect the performance of shares of 500 companies representing all major US industries and comprises shares of large companies traded on the NYSE Euronext or the NASDAQ OMX markets. A company?s weighting in the Underlying Index depends on its relative size, based on the combined value of a company?s readily available shares compared to other companies on the stock markets.