Since 1960, passenger kilometers flown per year throughout the world have increased by about 9%. This growth rate slowed down to about 5% after 1997 and forecasts indicate that this would remain the case for the next 10-15 years. The terrorist attacks of 11 September 2001, the SARS crisis and the Iraq war caused a marked decline in growth in 2001/2002. Based on similar experiences after the first Gulf War in 1991, we may conclude that crises of this sort merely delay growth by a few years.

However, from 2005, IATA (the International Air Transport Association) predicted a return to the previous growth trend (annual global growth of 5.6% in passenger kilometers).