May air transactions processed by mega travel agencies and settled through ARC fell 3.5 percent year over year,

according to ARC. Mega agencies include American Express Global Business Travel, BCD Travel, Carlson Wagonlit Travel, Egencia, HRG and Omega World Travel. Online travel agencies last month saw a 7.7 percent year-over-year rise in ARC air transactions, while the group of travel agencies classified by ARC as "other" posted a 0.4 percent decline. In total, U.S. travel agency air ticket transactions in May rose 1.6 percent year over year, according to ARC.