In the United States, a measure of the average change in prices over time in a fixed market basket of goods and services. Before 1978, only one CPI existed. Since then, the US Bureau of Labor Statistics has published CPIs for two population groups. The index used in this publication is for all US Urban Consumers (CPI-U), which covers approximately 80% of the non-institutionalized civilian population.
See also: Consumer Price Index, US Methodology.