Airlines still have a lot of older narrowbody aircraft to replace, with the Airbus A320ceo, A321ceo, and Boeing 737-800 leading the way. According to AviationValues, 59% of the aircraft within this segment are either the Airbus A320ceo or Boeing 737-800, both of which have been replaced by new-generation aircraft. However, more airlines are moving toward larger aircraft, with the A321neo’s backlog now surpassing the A320neo’s backlog. As of March, the split between older and newer generation aircraft was 70% to 30%, meaning there is still a lot of work to do for airlines to replace their older aircraft.