United States Consumer Price Index

The U.S. Consumer Price Index is a time series measure of the price level of consumer goods and services. The Bureau of Labor Statistics, which started the statistic in 1919, publishes the CPI on a monthly basis. The CPI is calculated by observing price changes among a wide array of products in urban areas and weighing these price changes by the share of income consumers spend purchasing them. The resulting statistic, measured as of the end of the month for which it is published, serves as one of the most popular measures of United States inflation; however, the CPI focuses on approximating a cost-of-living index not a general price index.
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