Global full-year 2012 passenger airline traffic grew 5.3 percent year over year,

according to the International Air Transport Association. That fell below the 2011 growth rate of 5.9 percent, but exceeded the 20-year average growth rate of 5 percent. Worldwide "demand in international markets expanded at a faster rate (6.0 percent) than domestic travel (4.0 percent)," according to IATA. Yet, North American carriers underperformed both averages, with "the slowest international passenger growth of any region at 1.3 percent" and U.S. domestic traffic up only 0.8 percent year over year, according to IATA. "The slowdown reflects the maturity and subdued economic growth of the U.S. market," according to IATA. Director general and CEO Tony Tyler projected "guarded optimism" for 2013 worldwide passenger growth, which IATA anticipated will "expand close to the 5 percent historical growth trend."