Gas prices in the three Northern New England states continued to drop over the past week.

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Maine saw the biggest decrease, with average retail prices falling near seven cents to an average of $1.98 per gallon.

New Hampshire didn't see as large a drop in averages prices as Maine, but continues to have the lowest gas prices at $1.91 a gallon, down from $1.95 a gallon a week earlier. Vermont's average price was $2.08, down 1.1 cents from a week ago.

Nationally, average prices dropped 6.5 cents per gallon to an average of $1.90 per gallon, according to gasoline price website GasBuddy.com.

Gas prices are markedly lower than one year ago. Maine prices are 17.5 cents lower per gallon now than they were at the same time one year ago.