The price of oil, or the oil price, generally refers to the spot price of a barrel () of benchmark crude oil—a reference price for buyers and sellers of crude oil such as West Texas Intermediate (WTI), Brent Crude, Dubai Crude, OPEC Reference Basket, Tapis crude, Bonny Light, Urals oil, Isthmus and Western Canadian Select (WCS). Oil prices are determined by global supply and demand, rather than any country's domestic production level. The global price of crude oil was relatively consistent in the nineteenth century and early twentieth century. This changed in the 1970s, with a significant increase in the price of oil globally. There have been a number of structural drivers of global oil prices historically, including oil supply, demand, and storage shocks, and shocks to global economic growth affecting oil prices. Notable events driving significant price fluctuations include the 1973 OPEC oil embargo targeting nations that had supported Israel during the Yom Kippur War resulting in the 1973 oil crisis, the Iranian Revolution in the 1979 oil crisis, and the financial crisis of 2007–2008, and the more recent 2013 oil supply glut that led to the "largest oil price declines in modern history" in 2014 to 2016. The 70% decline in global oil prices was "one of the three biggest declines since World War II, and the longest lasting since the supply-driven collapse of 1986." By 2015, the United States had become the third largest producer of oil and resumed exporting oil upon repeal of its 40-year export ban. The 2020 Russia–Saudi Arabia oil price war resulted in a 65% decline in global oil prices at the beginning of the COVID-19 pandemic. In 2021, the record-high energy prices were driven by a global surge in demand as the world recovered from the COVID-19 recession. By December 2021, an unexpected rebound in the demand for oil from United States, China and India, coupled with U.S. shale industry investors' "demands to hold the line on spending", has contributed to "tight" oil inventories globally. On 18 January 2022, as the price of Brent crude oil reached its highest since 2014—$88, concerns were raised about the rising cost of gasoline—which hit a record high in the United Kingdom. Structural drivers of global oil price According to Our World in Data, in the nineteenth and early twentieth century the global crude oil prices were "relatively consistent." In the 1970s, there was a "significant