All scales for questions about spend and income are asked in bands (e.g. €100-€200) rather than as exact values. This is to make it easier for respondents who may not always have perfect recall of exact amount, but typically will recall the price range they purchased in.
These bands are first built in Euro, so we have a common denominator across countries. Then the bands are converted to local currencies and rounded to meaningful local bands for use in the survey.
Conversion rates between Euros and local currencies are reviewed annually and the local bands updated where needed. The original Euro bands remain static over time.
Some insights require the use of scale mid-points in their calculation. E.g. to establish ‘average price’ paid, the band €100-€200 would contribute a value of €150 to the mean score calculation.
For more information, speak to your local GfK Account Manager or contact GfK support.