The appropriate value of a demand elasticity will vary in accordance to the context in which they are considered. In particular, the scope of the price change and the demand impact being assessed will have a key influence on its value, with demand typically being more sensitive to price when a greater amount of substitutes are available. 4 For example, the International Passenger Survey by the UK Office of National Statistics estimates that for UK residents travelling to Europe by air, the travel price represented 27% of the total journey cost in 2004. This proportion has declined in the last ten years, led by the growth of no-frills LCC airlines.04 - Air Travel Demand 19
For air transport there are five main levels (for the scope of the market) for which demand elasticities can be estimated