An average of 972,000 futures and options contracts per day changed hands, the bourse said, up by a fifth month-on-month, but down 26% compared with the same period a year ago.
The most active futures pairing was euro/dollar, with 7.66m contracts traded for the month, up by more than 40% on April. This was followed by the sterling, where 2.58m contracts traded, up 18.8%. Yen volumes were down 5% on April trading, at 2.3m.
Among the G10 currencies, the larger commodity currency pairs were the standout risers. The Aussie dollar posted a 52% rise month-on-month, with 2.55m contracts traded. The Canadian dollar jumped 38.5% from April, with 1.94m contracts changing hands. Euro volumes also led the options market, with 583,000 contracts traded, up 22.8% on April.