Source: expanded from Bowen, J. (2004) "World-Shapers: The Geographical Implications of Several Influential Jet Aircraft", paper presented at the 2004 Conference of the American Association of Geographers.
Average Airfare (roundtrip) between New York and London, 1946-2012 (in 2012 dollars)
Using a heavily traveled international air route, New York - London, as a frame of reference, it is clear that airfares have substantially declined, especially from the 1970s. During that decade, airfares declined by two thirds. The main reasons behind this decline are related to better and higher capacity aircrafts (especially the B747 with its economies of scale), general economic improvements (higher incomes) as well as the deregulation of the industry enabling higher competition, more frequent services and more flexibility for scheduling (from the 1980s). Thus, air travel shifted from being a mode available only for the wealthy to a mode affordable to the masses. There are however indications that airfares are unlikely to drop further in spite of improvements in aircraft design, fuel efficiency and safety. Fuel prices and airport congestion are important cost factors that have put pressures on airfares.