Diesel prices dropped more this week than any time during the last four years, according to the Energy Information Administration.
The national average diesel price soared to $3.96 a gallon — 13 cents per gallon higher than the same week last year.
The national average retail diesel price climbed for the second consecutive week, rising 1.2 cents to $3.695 a gallon during the week.
The national average retail diesel price fell 5.3 cents to $4.004 for the week ended Monday, May 14.
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