5 years behind becomes 3 years behind. China is expanding their manufacturing abilities faster than the US. Soon they will surpass the US. Look no further than their generic consumer electronics manufacturing.
CFM LEAP, latest short-to-medium-haul airliner engine from CFM (GE+Safran) is from 2013 (first run). Its predecessor, CFM56, is from 1974 (first run) and saw a few evolutions, including as late as 2009.