In the United States, deposit money issued by private banks grew rapidly in the late nineteenth and the twentieth centuries. From a historical perspective, a now well-established form of electronic money is the bank deposit stored on the computers of the banking industry.
Between 1990 and 2000, although spot prices ranged between $ and $ per barrel, distant futures exhibited little variation. Currently prices for delivery in 2010 of light sweet crude, roughly equal to West Texas intermediate, have risen to more than $ per barrel. A similar pattern is evident in natural gas.