The review of previous studies helps to provide a greater understanding of air travel price elasticities and provides important insights for the new econometric analysis by InterVISTAS Consulting (discussed in the next chapter). The review looked at several academic and government commissioned studies . The different studies7 produced a wide range of air travel price elasticity estimates, varying in accordance with the markets analysed, the time period assessed, the methodology used and the available data. Even within some particular studies, a range of elasticities are estimated for different markets. For example, a commonly referenced study by Gillen, Morrison and Stewart8 found demand elasticities ranging from -0.1 to -1.7, depending on the relevant market. It identified various elasticity estimates for several distinct markets for air travel, such as: