Updated

U.S. retail gasoline prices hit a five-month low, with the cost at the pump falling 11.8 cents over the last week to an average $2.73 a gallon, the government said on Tuesday.

The national price for regular unleaded gasoline is down 34 cents from a year ago, according to the federal Energy Information Administration 's weekly survey of 800 service stations.

It was first time in a year that current pump prices were lower than 12 months earlier, but that was due to fuel costs jumping to a still-record $3.07 a gallon a year ago when Hurricane Katrina struck the Gulf Coast and disrupted petroleum supplies.

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Gasoline is now at the lowest level since April 10 and has declined 27 cents a gallon in the last three weeks alone, the Energy Department's analytical arm said.

With the peak summer driving season now over and gasoline supplies plentiful, motor fuel prices are expected to keep falling.

Cheaper crude oil, which accounts for about half the cost of making gasoline, should also mean more price breaks at the pump for drivers.

Oil for delivery in October settled down 59 cents to $68.60 a barrel on Tuesday at the New York Mercantile Exchange,

Separately, the EIA said the price truckers paid for diesel fuel dropped 6 cents to $2.97 a gallon, up 7 cents from a year ago but the first time diesel fell below $3 in five weeks.

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