Index numbers constitute the basic instrument to synthesize economic statistics so that the formulas used allow to express and describe, for example, the economic growth of a country or the inflation rate of an economy, and to make international comparisons. If different formulas are used, the results differ, and the comparisons are not valid. Hence the importance of knowing the formulas that are used and promoting common practices that harmonize and standardize measurements. Although index numbers are linked to macroeconomics, its theoretical foundation is based on microeconomics.
