An emergency supply of oil that can be borrowed against in the event that oil supplies are disrupted due to a war, a strike in oil producing countries, or restrictions in production by an oil cartel. SPR is administered by the U.S. Department of Energy and was begun after oil prices rose sharply in 1973–1974 driving up the price of oil and its derivatives, such as gasoline. The rise in energy prices caused inflation and helped to weaken the U.S. economy. In December 2002, the SPR had a 598-million-barrel reserve.