It's the oilopoly, stupid. "Increases in the 'spot' market price of crude oil -- which is the highest price a major oil company would pay for crude oil -- accounted for only 12 cents per gallon [of rising gasoline prices]. California's percentage sales tax increased fuel prices by another four cents per gallon.
More than 40 cents of the 60-cent increase in gasoline prices over 3 1/2 months is attributable to increased refinery and marketing profit margins for the oil companies." —
The Foundation for Taxpayer and Consumer Rights