AASHTO Journal, 1 May 2015
The average U.S. retail price of gasoline jumped 8.5 cents a gallon in the week ending April 27, the Energy Information Administration said, while pump prices for diesel fuel rose a more moderate 3.1 cents.

Those latest price changes follow the pattern of the previous week, leaving gasoline about 16 cents higher than on April 13 while diesel is up nearly 6 cents over that period.
The AAA motor club, which tracks prices daily, said the recent spike in gas prices “has been the product of rising global crude prices, the seasonal switch to summer-blend gasoline and regional refinery issues, particularly on the West Coast.”
Producers have until May 1 to complete their changes to higher-cost summer blends, AAA said.
Even with the sizable April increases, the average pump price of gasoline at $2.57 a gallon on April 27 was down by more than $1.14 from the same point in 2014, the EIA said, which leaves drivers of most household vehicles paying about a third less for motor fuel than a year ago.
Diesel continued its pattern of moving less sharply than gasoline. Its April 27 average price of $2.81 a gallon was more than $1.16 below its year-ago level.
Since most on-highway diesel fuel is used to power commercial trucks, and truck lines quickly adjust fuel surcharges for the latest EIA levels, the freight supply chain is paying much less in fuel fees in 2015 than last year.