The Consumer Price Index for All Urban Consumers (CPI-U) in the Chicago-Gary-Kenosha area decreased 0.4 percent in December, the U.S. Bureau of Labor Statistics reported today. Assistant Commissioner for Regional Operations Charlene Peiffer noted that in December the energy index fell 2.3 percent, while the food index increased 0.1 percent. The all items less food and energy index declined 0.3 percent over the month. Among the indexes within the all items less food and energy category, prices were lower for shelter, apparel, and medical care, but higher for new and used motor vehicles and recreation. (Data in this report are not seasonally adjusted. Accordingly, month-to-month changes may reflect the impact of seasonal influences.)

Over the last 12 months, the Chicago area all items CPI-U increased 1.7 percent. (See chart 1 and table A.) Energy costs rose 7.4 percent over the year, primarily due to an increase in gasoline prices. For the same period, the food index increased 0.8 percent. The all items less food and energy index was 1.4 percent higher over the year. (See table 1.)

Food

Food prices were 0.1 percent higher in December. The food at home index (groceries) increased 0.2 percent, while the food away from home (restaurant, cafeteria, and vending purchases) index was unchanged. Within the food at home group, prices were higher in December for eggs; breakfast cereal; and rice, pasta, and cornmeal. In contrast, the index for other processed fruits and vegetables including dried was lower.

From December 2016 to December 2017, the food index increased 0.8 percent. Grocery prices rose 0.4 percent, and food away from home prices rose 1.2 percent over the year.

Energy

The energy index declined 2.3 percent in December. The index for gasoline fell 6.2 percent. In contrast, the index for utility (piped) gas service rose 3.8 percent, while the electricity index was unchanged.

Over the year, the Chicago area energy index rose 7.4 percent. From December 2016 to December 2017, the indexes rose for gasoline (10.7 percent), electricity (6.3 percent), and utility (piped) gas service (2.2 percent).

All items less food and energy

The index for all items less food and energy decreased 0.3 percent in December. Among the index’s components, prices were lower for shelter (-0.5 percent), apparel (-3.1 percent), and medical care (-0.6 percent). Prices were higher for new and used motor vehicles and recreation (1.0 percent).

Over the year, the index for all items less food and energy increased 1.4 percent. Increases in the indexes for shelter (2.2 percent) and recreation (5.8 percent), were major contributing factors.

Table A. Chicago CPI-U 1-month and 12-month percent changes, all items index, not seasonally adjusted

Month	2013		2014		2015		2016		2017
	1-month	12-month	1-month	12-month	1-month	12-month	1-month	12-month	1-month	12-month
January	0.2	1.2	0.9	1.2	-0.2	0.4	0.8	0.9	0.7	1.8
February	1.1	2.3	0.5	0.7	0.0	-0.2	-0.2	0.7	0.1	2.2
March	-0.1	0.9	1.1	1.9	0.7	-0.6	0.1	0.2	-0.1	2.0
April	0.0	0.9	0.5	2.4	0.1	-0.9	0.6	0.7	0.4	1.7
May	0.5	1.5	-0.1	1.8	0.3	-0.5	0.0	0.3	0.2	1.8
June	0.1	1.7	0.4	2.0	0.2	-0.7	0.5	0.7	0.0	1.3
July	-0.2	1.7	-0.4	1.9	-0.1	-0.5	-0.8	-0.1	0.0	2.2
August	0.1	1.1	0.1	1.9	0.4	-0.1	0.2	-0.2	0.3	2.3
September	-0.2	0.7	0.0	2.1	-0.3	-0.4	0.6	0.6	0.4	2.1
October	-0.3	0.5	-0.4	2.0	-0.1	-0.2	0.1	0.8	-0.4	1.6
November	-0.3	0.6	-0.8	1.6	-0.4	0.2	0.2	1.5	0.4	1.8
December	-0.3	0.5	-0.4	1.5	-0.6	0.0	-0.2	1.9	-0.4	1.7

The January 2018 Consumer Price Index for Chicago is scheduled to be released on Wednesday, February 14, 2018.

Technical Note

The Consumer Price Index (CPI) is a measure of the average change in prices over time in a fixed market basket of goods and services. The Bureau of Labor Statistics publishes CPIs for two population groups: (1) a CPI for All Urban Consumers (CPI-U) which covers approximately 89 percent of the total population and (2) a CPI for Urban Wage Earners and Clerical Workers (CPI-W) which covers 28 percent of the total population. The CPI-U includes, in addition to wage earners and clerical workers, groups such as professional, managerial, and technical workers, the self-employed, short-term workers, the unemployed, and retirees and others not in the labor force.

The CPI is based on prices of food, clothing, shelter, and fuels, transportation fares, charges for doctors' and dentists' services, drugs, and the other goods and services that people buy for day-to-day living. Each month, prices are collected in 87 urban areas across the country from about 6,000 housing units and approximately 24,000 retail establishments--department stores, supermarkets, hospitals, filling stations, and other types of stores and service establishments. All taxes directly associated with the purchase and use of items are included in the index.

The index measures price changes from a designated reference date (1982-84) that equals 100.0. An increase of 16.5 percent, for example, is shown as 116.5. This change can also be expressed in dollars as follows: the price of a base period "market basket" of goods and services in the CPI has risen from $10 in 1982-84 to $11.65. For further details see the CPI home page on the Internet at www.bls.gov/cpi and the BLS Handbook of Methods, Chapter 17, The Consumer Price Index, available on the Internet at www.bls.gov/opub/hom/pdf/homch17.pdf.

In calculating the index, price changes for the various items in each location are averaged together with weights that represent their importance in the spending of the appropriate population group. Local data are then combined to obtain a U.S. city average. Because the sample size of a local area is smaller, the local area index is subject to substantially more sampling and other measurement error than the national index. In addition, local indexes are not adjusted for seasonal influences. As a result, local area indexes show greater volatility than the national index, although their long-term trends are quite similar. Note: Area indexes do not measure differences in the level of prices between cities; they only measure the average change in prices for each area since the base period.

The Chicago-Gary-Kenosha, Ill.-Ind.-Wis. consolidated area covered in this release is comprised of Cook, DeKalb, DuPage, Grundy, Kane, Kankakee, Kendall, Lake, McHenry, and Will Counties in Illinois; Lake and Porter Counties in Indiana; and Kenosha County in Wisconsin.

Information in this release will be made available to sensory impaired individuals upon request. Voice phone: (202) 691-5200; Federal Relay Service: (800) 877-8339.