(WASHINGTON) -- Drivers in the U.S. are paying more to fill up their gas tanks. New gas figures from the U.S. Department of Energy are out and show that the price for regular unleaded is up an average of about 15 cents nationwide to $3.64. That's 21 cents more than this time last year.
The Midwest has seen prices increase 23 cents in the past week. Gasoline in California is the most expensive at $4.02 per gallon of unleaded.
The increase reverses what happened several weeks ago in parts of the country.
"In some states in the Great Lakes [region], gas prices had dropped a dollar a gallon in the preceding three weeks," said Gasbuddy.com senior petroleum analyst Patrick DeHaan. "Now we're seeing prices go right back up across much of the nation due to a rise in oil prices."
Crude oil is more scarce, and the growing political tension in Egypt is causing concerns about oil from that region.
"This is the free market at work. You have an increase in gasoline and oil consumption in the summer months when Americans typically take to the road to travel and for vacations," DeHaan said.
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