OIIL tracks the Bloomberg WTI Crude Oil Total Return SubindexSM (the "Index"), which is a single commodity subindex of the total return version of the Bloomberg Commodity IndexSM (the "Base Index"). The Index is intended to reflect the returns that are potentially available through an unleveraged investment in rolling West Texas Intermediate crude oil futures contracts, plus the Treasury Bill rate of interest that could be earned on funds committed to the trading of the underlying contracts. The Base Index reflects the returns that are potentially available through an unleveraged investment in the futures contracts on physical commodities constituting the underlying commodity index. The Base Index was previously known as the Dow Jones–UBS Commodity IndexSM. The Index is a total return index and was launched on July 14, 1998.