US gas prices have risen by an average 12 cents a gallon nationwide over the past two weeks, reflecting higher crude oil prices, but a new survey shows the rate of increase is slowing.
The national average for a gallon of regular gasoline rose to $3.8148 as of March 9, according to the Lundberg Survey of gasoline retailers in the continental United States.
Drivers in Denver saw the lowest pump price at $3.36 per gallon, compared with $4.35 in Los Angeles, the nation's highest, MSNBC reported.
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The national average price jumped 18.6 cents in the previous survey, according to CNN.
"There are reasons to believe the rate of increase may slow again," survey editor Trilby Lundberg told Reuters. "If crude does not jump again immediately, then the gasoline market will be able to peak soon."
While crude oil is the biggest factor, events on the West Coast are helping keep retail prices up as well, she told CNN.
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"Gasoline prices would like to peak soon because there is too much gasoline supply versus demand," Lundberg told CNN, "except on the West Coast due to refinery maintenance projects."
Higher prices on the West Coast "attract gallons from elsewhere in the country," impacting supply nationwide, she told CNN. "So it creates a slightly tighter gasoline market for now."
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The Lundberg Survey tabulates prices at thousands of gas stations nationwide. It latest figures were collected Friday.