airline industry in response to wartime needs also led to higher demand for labor. Increasingly more pilots, flight staff, engineers, and researchers were needed to operate the aircraft as well as develop advanced technology, leading to increased job creation. During this time, unemployment rates decreased significantly, dropping to nearly the full employment rate. Post WWII The end of World War II, immediately followed by demobilization, led to airplane companies losing a total of $35 million in 1946 in sales and $115 million in 1947. There was once again an excess in aircraft supply post-war and not a high enough corresponding demand. Accordingly, unemployment increased slightly by 2% in the 2 years following the end of World War II. However, with the technological improvements in passenger travel safety and comfort, accompanied by an increasing demand in commercial aviation, the airline industry was soon driving revenues that were 500% of its revenues by 1945. This increase in commercial demand was also fueled by an increase in consumer confidence in airlines, reinforced by the creation of the Federal Aviation Administration in 1958, which managed aviation safety. Economist Alfred Kahn became the chairman of the Civil Aeronautics Board in the mid-1970s, which eventually led to Congress passing the Airline Deregulation Act of 1978. This allowed for free market competition in the airline industry, to meet the pressure of the decreasing world price of air travel. This ultimately allowed the U.S. airline industry to operate competitively in the international market. Twenty-first century The American airline industry has suffered significantly as a result of the terrorist attacks of September 11. The attacks of September 11 dramatically decreased consumer confidence in the airline industry. The airline industry lost more than $330 million each day within the first week of the attack, totaling losses between $1 and $2 billion. In the following years, the decrease in demand accompanied by the decreasing price of air travel reduced revenues significantly. The price of fuel has also been rising, further increasing airlines' losses by $180 million per year. Another large part of airline expenses comes from wages for employees, which make up 40% of airlines' expenses. To compensate for rising costs and decreasing revenues, airlines have decreased the number of planes in service and thus have also laid off workers, negatively impacting the economy's unemployment rate. Contribution to GDP and employment The Federal Aviation Administration (FAA) in 2009 found that commercial