Middle East crude for immediate delivery traded at its biggest premium in two years to later shipments last month after Royal Dutch Shell Plc (RDSA) bought an unprecedented number of cargoes. The price gap between the earliest loadings of the benchmark Dubai grade and those for two months later climbed to $2.82 a barrel on Nov. 21, the widest spread since 2011, according to data compiled by Bloomberg. The increase coincided with Shell’s purchase of 12 million barrels last month via the Middle East crude price-setting system conducted by Platts, a unit of McGraw-Hill Financial Inc. (MHFI) The premium for prompt cargoes, a market structure known as backwardation , influences the level at which Middle East exporters including Saudi Arabian Oil Co. set official monthly prices for buyers in Asia, according to industry consultants KBC Energy Economics and JBC Energy GmbH. The growing spread shows how deals made in […]