The figures on purchasing power presented here are based on income figures from the tax registration combined with figures from the Labour Force Survey. This link makes it possible to calculate the year-on-year changes in purchasing power for specific socio-economic groups (e.g. the most common occupations). As the figures are median changes in purchasing power, the differences between 2008 and 2009 are not the result of the application of the less robust average.
Changes in purchasing power are not only caused by developments of wages and prices, but also by changes in working hours and in household composition.