1. Alphabetically arranged list of items (such as names or terms) given at the end of a printed text with page numbers on which the item can be found.
2. Statistical device which summarizes a collection of data (usually related to the price or quantity of a 'basket' of goods and services) in a single base figure. This composite figure serves as a benchmark for measuring changes in the price or quantity data over a period (month, quarter, year). Usually, the base is assigned an arbitrary value of 100 and all subsequent data is expressed in relation to this base. For example, the consumer price index (CPI) of a year might stand at 95 (to indicate a fall of 5 percent in the prices) or 105 (to indicate an increase of 5 percent in the prices).
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