In statistics and research design, an index is a composite statistic – a measure of changes in a representative group of individual data points, or in other words, a compound measure that aggregates multiple indicators. In economics and finance, an index is a statistical measure of change in a representative group of individual data points. These data may be derived from any number of sources, including company performance, prices, productivity, and employment. Economic indices track economic health from different perspectives. There is a substantial body of economic analysis concerning the construction of index numbers, desirable properties of index numbers and the relationship between index numbers and economic theory. A number indicating change in magnitude, as of price, wage, employment, or production shifts, relative to the magnitude at a specified point usually taken as 100. We will discuss some of the most influential global performance indices used as indicators to understand the condition and performance of different countries and regions.