a possible Sydney-Los Angeles passenger willing to pay $1300? Airlines have to make hundreds of thousands of similar pricing decisions daily. The advent of advanced computerized reservations systems in the late 1970s, most notably Sabre, allowed airlines to easily perform cost-benefit analyses on different pricing structures, leading to almost perfect price discrimination in some cases (that is, filling each seat on an aircraft at the highest price that can be charged without driving the consumer elsewhere). The intense nature of airfare pricing has led to the term "fare war" to describe efforts by airlines to undercut other airlines on competitive routes. Through computers, new airfares can be published quickly and efficiently to the airlines' sales channels. For this purpose the airlines use the Airline Tariff Publishing Company (ATPCO), who distribute latest fares for more than 500 airlines to Computer Reservation Systems across the world. The extent of these pricing phenomena is strongest in "legacy" carriers. In contrast, low fare carriers usually offer pre-announced and simplified price structure, and sometimes quote prices for each leg of a trip separately. Computers also allow airlines to predict, with some accuracy, how many passengers will actually fly after making a reservation to fly. This allows airlines to overbook their flights enough to fill the aircraft while accounting for "no-shows", but not enough (in most cases) to force paying passengers off the aircraft for lack of seats, stimulative pricing for low demand flights coupled with overbooking on high demand flights can help reduce this figure. This is especially crucial during tough economic times as airlines undertake massive cuts to ticket prices to retain demand. Over January/February 2018, the cheapest airline surveyed by price comparator rome2rio was now-defunct Tigerair Australia with $0.06/km followed by AirAsia X with $0.07/km, while the most expensive was Charterlines, Inc. with $1.26/km followed by Buddha Air with $1.18/km. For the IATA, the global airline industry revenue was $754 billion in 2017 for a $38.4 billion collective profit, and should rise by 10.7% to $834 billion in 2018 for a $33.8 billion profit forecast, down by 12% due to rising jet fuel and labor costs. The demand for air transport will be less elastic for longer flights than for shorter flights, and more elastic for leisure travel than for business travel. Airlines often have a strong seasonality, with traffic low in winter and peaking in summer. In Europe the most extreme market