The price consumers pay for gasoline is determined by the cost components that make up the retail price of gasoline, including crude oil, refining, distribution and marketing, and taxes. Crude oil is the largest and most volatile cost component. Large changes in the price of crude oil are often a result of economic factors, as evidenced by the precipitous drop during the Great Recession in 2008. Refining, as well as distribution, can be affected by weather events, maintenance, or transitions for seasonal fuel blends. Taxes, including both state and federal, are the most stable of the cost components of retail gasoline.