The Consumer Price Index (CPI) is a measure of the average change over time in the prices paid by urban consumers for a market basket of consumer goods and services. Produced monthly by the Bureau of Labor Statistics (BLS), the CPI uses a “market basket,” or a sample of goods and services that consumers purchase for day-to-day living, and weighs each item on the basis of the amount of spending reported by a sample of families and individuals. Widely used as a measure of inflation, the CPI provides information about price changes in the nation’s economy and can be used by government, business, labor, and private individuals as a guide to making economic decisions. Over the last 12 months, the index for all items less food and energy has slowly accelerated. In contrast, the all-items index has decelerated since a 12-month increase of 3.9 percent in September 2011. The September 2011 increase capped a run of steady acceleration in the all-items index that began in December 2010. Despite the contrast, the all-items index increased at a higher rate than the index for all items less food and energy in the first quarter of 2012. This summary compares price changes in the CPI for detailed categories of goods and services over the first quarter of 2012 with those in 2011.