WASHINGTON (Reuters) - While U.S. retail gasoline prices have declined for seven weeks in a row, they are still at the highest level ever recorded by the government heading into the busy Christmas travel week, the Energy Department said on Monday. The national pump price for regular unleaded gasoline fell 3.2 cents over the last week to $1.815 a gallon, up 33 cents from a year ago, according to a survey of service stations by the U.S. Energy Information Administration. A record 62.7 million Americans will travel 50 miles or more from home this Christmas and New Year's Day, according...