The Consumer Price Index (CPI) is the measure of the average change over time in the prices paid by urban consumers for a fixed market basket of consumer goods and services. The CPI provides a way for consumers to compare what a market basket of goods and services cost this month with what the same market basket cost a month or year ago. The CPI affects all Americans because of the way it is used. The three major uses are as a economic indicator, as a deflator of other economic series, and as a means of adjusting dollar values. The CPI reflects the spending patterns for each of the two population groups: All Urban Consumers (CPI-U) and Urban Wage Earners and Clerical Workers (CPI-W). Th