The national average price for diesel fuel continued its steady decline, falling 3.5 cents per gallon to $1.318, its lowest price of 2001, according to the Department of Energy.At this time last year, the price was 31.2 cents a gallon higher, the report from the DOE’s Energy Information Administration (EIA) said. The previous low this year was $1.347 per gallon on July 30.The price of diesel fuel is important to the trucking industry because a large number of trucks run on diesel fuel. The price of fuel impacts the price of providing trucking services.Since the Sept. 11 terrorist attacks, the demand for travel and transportation services has declined significantly, forcing a drop in the prices of crude oil and other petroleum products such as diesel fuel and gasoline.The price fell in every one of the EIA’s Petroleum Administration for Defense Districts (PADD) and each subdistrict as well. The largest drop in a single PADD was in the Midwest, where the price fell 4.4 cents per gallon to $1.329.The drop ranged from the 4.4 cents per gallon decline in the Midwest, to the 2.8 cents fall-off on the East Coast. Outside of the Midwest, the West Coast saw the largest drop in prices, followed by the Rocky Mountains and the Gulf Coast, with the smallest decrease on the East Coast.The cheapest average regional price was along the Gulf Coast, where the price was $1.255 a gallon.The EIA surveys 350 fueling stations at the start of each week, and usually reports the results on the same day that it polls the stations.