WASHINGTON - The average U.S. retail gasoline price fell 33.3 cents over the last week to $3.15 a gallon, the biggest price decline ever recorded by the government, the Energy Department said on Tuesday, according to Reuters.

The old record decline of 16.9 cents a gallon occurred during the week of the Sept. 12, 2005, when fuel costs fell after the government announced it would release millions of barrels of emergency crude oil to help replace petroleum supplies disrupted by Hurricane Katrina.

The national price for regular unleaded gasoline is the cheapest since Feb. 25, but it remained up 39 cents from a year ago, the department's Energy Information Administration said in its weekly survey of service stations.