Definition: An index designed to measure the change in price of a fixed market basket of goods and services. The market basket of goods and services is representative of the purchases of a typical urban consumer. The index is intended to measure pure price change only; attempts are made to remove changes in price resulting from changes in quality.Source: U.S. Department of Labor; Bureau of Labor StatisticsFrequency: MonthlyAvailability: Generally available the second week of the month immediately following the month for which data is being released; always released after the Producer Price Index.Reason: The rate of change of the CPI is one of the key measures of inflation for the U.S. economy. Acceleration or deceleration of inflation may signal that a change in monetary policy may be appropriate.