The average price of a gallon of gasoline in the United States dropped 12 cents in the past three weeks to its lowest point in nearly a year, driven by the latest round of falling oil prices, according to the Lundberg survey released on Sunday.

Prices fell to an average of $3.26 per gallon for regular grade gasoline, according to the survey conducted on Oct. 10. Prices have fallen for the past 16 weeks, survey publisher Trilby Lundberg said.

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The price of a gallon is nearly 13 cents below what it was a year ago and is at its lowest point since Nov. 22, she added. The price peaked on May 2 and is down 46.5 cents since then.