Measuring inflation is hard for a variety of reasons, and it gets even harder when you try to compare across countries and regions. Some of the reasons include methodological choices in averaging, weighting, how housing and transportation are accounted for, how urban and rural consumers are included, and many others. There is a measure called the Harmonized Index of Consumer Prices (HICP) that is used to try to compare across countries and regions. This differs from the U.S. CPI in a variety of ways.