The average U.S. retail gasoline price fell to $2.38 a gallon, dropping for the seventh week in a row, and could decline another 23 cents by mid-October, the government said on Monday.

The national price to fill up with regular unleaded gasoline was down 11.9 cents over the last week and 43 cents lower from a year ago, according to the federal Energy Information Administration's weekly survey of service stations.

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The average pump price has now fallen seven weeks in a row, dropping 66 cents since hitting a summer high of $3.04 a gallon on Aug. 7.

It is the second-largest unbroken drop in gasoline prices since pump costs fell 78 cents a gallon over a nine-week period beginning last October after Hurricane Rita hit, the EIA said.

U.S. drivers could see the national fuel price fall as low as $2.15 a gallon over the next two or three weeks, once cheaper spot prices for motor fuel are finally passed on to consumers at the pump, according to EIA analyst Mike Burdette.

Fuel prices are falling because of lower crude oil, which accounts for about half the cost of making gasoline. While oil costs were up 90 cents to $61.45 a barrel in Monday trading at the New York Mercantile Exchange, that is still way down from the record $78.40 a barrel reached in mid July.

Retail gasoline prices at some stations across the country have already dropped below $2 a gallon, but the EIA has said it does not expect the national pump price to break the $2 threshold unless crude oil continues to decline sharply.

In the EIA's new weekly survey, West Coast service stations had the most expensive gasoline by region, down 8.8 cents to $2.72 a gallon. Los Angeles had the highest pump price among cities at $2.78 a gallon, down 8.8 cents.

The cheapest gasoline was in the Midwest at $2.21 a gallon, down 11.2 cents. Cleveland had the best deal at the pump at $2.11, down 11.2 cents.

Separately, the EIA said the price truckers paid for diesel fuel fell 11.8 cents to $2.60 a gallon, down 20 cents from a year ago and the lowest since March 27.

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