The national average from a gallon of Jet-A totaled $6.72 in May, down 26 cents when compared to April averages and down $1.32 from a year ago, according to a survey by the Aviation Research Group U.S. The price declined in all eight FAA regions, with the largest decrease found in the Eastern and New England regions, with a drop of 53 cents from April. The smallest monthly decline was found in the Central region with a 4-cent decrease.