The average cost for a gallon of diesel for the week ending Sept. 17, 2006 dropped 14.4 cents to $2.713, according to the Energy Information Administration. This makes the average price 1.9 cents lower than for the same week last year. And that marks the first time prices have been lower than a year before since the week ending March 21, 2004, an EIA economist told FleetOwner.

For the week ending March 21, 2004, diesel prices were $1.641.

All regions posted a double-digit decline in prices, but the Rocky Mountain region saw the steepest drop, down 18.4 cents to $3.052. In spite of this, the Rocky Mountain region remains the most expensive in which to fill up. Prices were the most stable in the Central Atlantic region, sliding 11.4 cents to $2.844. The cheapest region in which to fill up was the Midwest at $2.624 after a 16.3-cent rollback.

“Crude oil prices have been falling a lot,” Neil Gamson, EIA economist told FleetOwner, noting that prices had fallen since a $77/barrel high over the summer to about $63/barrel. Hurricanes Katrina and Rita, which had devastated the nation’s energy infrastructure and caused massive price spikes, was also a factor in the year-over-year price relief since this year the hurricane season is relatively quiet so far, Gamson added.

“Supply is adequate and right now there’s no competition from heating oil because the weather has been mild,” Gamson said. “If it gets cold in November or December in the East, we expect diesel prices will go up.”

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