United States Commodity Index Fund ( USCI ): This fund's underlying index, the SummerHaven Dynamic Commodity Index Total Return, is an equal-weighted benchmark of 14 commodities. When the Bureau of Labor Statistics analyzed price movements in four commodities-crops, animal slaughter and processing, dairy, and oil and gas-only the petroleum products substantially contributed to inflation. DBC was designed to make the best of the futures curve-finding the most backwardation and the least contango-while GSG is limited to simply rolling forward its front month contracts to the next sequential delivery.