The Consumer Price Index (CPI) is a statistical measure of the evolution of the prices of goods and services consumed by the population that reside in family dwellings in Spain.

The combination of goods and services that conform the shopping basket is basically obtained from the consumption of families, and the importance of each one of these within the calculation of the CPI is determined by said consumption.

As of January 2002 the CPI methodology was completely renewed. The methodological changes introduced in this System has made the CPI indicator more dynamic, adapting better to the evolution of the market, given that it is possible to update the weightings more frequently. Furthermore, it is possible to include new products in the shopping basket when consumption becomes significant.