The current price is the highest since Aug. 25, 2008, when it was $4.158 a gallon.
The price increased 2.9 cents in the most recent period and 27.5 cents over the last seven weeks.
The latest price rocketed past $4 a gallon to $4.051. A year ago it was 33.5 cents higher.
It was the sixth increase in the last seven weeks, during which the diesel price has risen 17.7 cents.
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