the Platts and Argus assessed values at the time. Development of the physical WTI market The US governmental decontrol of oil prices on January 28, 1981, marked the beginning of the physical WTI Crude Oil spot market. Under the previous US Emergency Petroleum Allocation Act of 1973, WTI crude oil traded under a variety of spot prices split into various categories set by the price controls. After the price decontrol, WTI graded crude oil traded under spot prices centered around spot prices at Cushing, Oklahoma, Midland, Texas, and Houston, Texas (specifically at the Magellan East Houston "MEH" Terminal). Oil price collapses during 1985-1986 significantly reduced local oil production around Cushing, and linked Gulf Coast imported crude oil supplies into the Cushing region and the WTI market. The growth of the WTI spot market came in tandem with the growth of the WTI futures market. The volatility of WTI spot prices lead to the development of WTI futures contracts, while the adoption of the WTI futures contracts as hedging tools by producers and refiners worldwide lead to the worldwide adoption of assessed physical WTI spot prices as benchmark prices for crude. Global adoption of WTI assessed prices as oil benchmark prices Price Reporting Agencies (PRAs), such as Platts and Argus Media, compiled assessment prices of WTI based on prices of spot transactions starting in 1981. Eligible spot transaction prices at Cushing, Oklahoma, is typically reported as WTI, while eligible spot transactions at Midland, Texas, and Houston, Texas (at the MEH Terminal) are reported as WTI Midland, and WTI Houston respectively. The development of WTI spot and futures markets led crude oil producers around the world to use assessed WTI prices as a benchmark in oil pricing. For example, in 2008, Saudi Arabia, Kuwait, Iraq, Colombia, and Ecuador based their crude oil selling prices on either the Platts WTI Mnth 1 index or the Platts WTI Mnth 2 index (the assessed prices of transactions with delivery in the next deliverable month or the second deliverable month). Subsequently, Saudi Arabia, Kuwait, and Iraq started using the Argus Sour Crude Index (ASCI) as their price index in 2009, but the ASCI index itself is priced in relation to WTI futures with a differential, which imply those countries still effectively benchmark their crude oil selling prices to WTI. NYMEX WTI Crude Oil futures contract The volatility of crude oil prices after the US oil price