The aim is for the investment to reflect the performance of the S&P 500 2x Inverse Daily Index (Index) which provides two times the opposite performance of the S&P 500 Index (Underlying Index) on a daily basis plus a rate of interest. This means that the level of the Index should rise at double the rate the Underlying Index falls and fall at double the rate the Underlying Index rises. The interest rate added to the Index level is based on three times the rate at which banks in London lend US dollars to each other overnight. 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.