The Consumer Price Index for All Urban Consumers (CPI-U) in the Chicago-Naperville-Elgin area increased 0.4 percent in September, the U.S. Bureau of Labor Statistics reported today. Assistant Commissioner for Regional Operations Charlene Peiffer noted that food prices rose 1.1 percent while the energy index decreased 0.1 percent in September. The all items less food and energy index increased 0.3 percent over the month. Within the all items less food and energy category, prices were higher for apparel; shelter; and household furnishings and operations over the month, but fell for tuition, other school fees, and childcare. (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 1.6 percent. (See chart 1 and table A.) Over the year, the energy index rose 5.8 percent. The rise in the energy index was primarily due to higher gasoline prices. The food index and the all items less food and energy index rose 2.0 percent and 1.2 percent, respectively, over the year. (See table 1.)

Food

Food prices rose 1.1 percent in September. Of the two components within the food index, prices for food at home (groceries) increased 1.5 percent and prices for food away from home (restaurant, cafeteria, and vending purchases) rose 0.6 percent. Within the food at home group, indexes were higher in September for snacks; frozen and freeze dried prepared foods; and other meats. Prices were lower for carbonated drinks and uncooked beef steaks.

From September 2017 to September 2018, the food index increased 2.0 percent. Over the year, costs for food away from home rose 4.0 percent, while grocery prices were 0.4 percent higher.

Energy

The energy index decreased 0.1 percent in September, due to declines in the electricity index (-1.5 percent) and the utility (piped) gas service index (-0.4 percent). During the same period, gasoline prices rose 0.7 percent.

Over the year, the Chicago area energy index rose 5.8 percent. From September 2017 to September 2018, gasoline prices and the utility (piped) gas index rose 12.0 percent and 0.7 percent, respectively. The electricity index declined 2.4 percent over the year.

All items less food and energy

The index for all items less food and energy increased 0.3 percent in September. Among the index’s components, prices were higher for apparel (4.7 percent); shelter (0.4 percent); and household furnishings and operations (2.0 percent), but lower for tuition, other school fees, and childcare (-2.5 percent).

Over the year, the index for all items less food and energy rose 1.2 percent. A 3.0-percent increase in the index for shelter was the major contributing factor.

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

Month	2014		2015		2016		2017		2018
	1-month	12-month	1-month	12-month	1-month	12-month	1-month	12-month	1-month	12-month
January	0.9	1.2	-0.2	0.4	0.8	0.9	0.7	1.8	0.8	1.8
February	0.5	0.7	0.0	-0.2	-0.2	0.7	0.1	2.2	0.0	1.6
March	1.1	1.9	0.7	-0.6	0.1	0.2	-0.1	2.0	0.0	1.8
April	0.5	2.4	0.1	-0.9	0.6	0.7	0.4	1.7	0.7	2.1
May	-0.1	1.8	0.3	-0.5	0.0	0.3	0.2	1.8	0.4	2.3
June	0.4	2.0	0.2	-0.7	0.5	0.7	0.0	1.3	-0.2	2.2
July	-0.4	1.9	-0.1	-0.5	-0.8	-0.1	0.0	2.2	-0.3	1.9
August	0.1	1.9	0.4	-0.1	0.2	-0.2	0.3	2.3	0.1	1.7
September	0.0	2.1	-0.3	-0.4	0.6	0.6	0.4	2.1	0.4	1.6
October	-0.4	2.0	-0.1	-0.2	0.1	0.8	-0.4	1.6
November	-0.8	1.6	-0.4	0.2	0.2	1.5	0.4	1.8
December	-0.4	1.5	-0.6	0.0	-0.2	1.9	-0.4	1.7

The October 2018 Consumer Price Index for Chicago is scheduled to be released on Wednesday, November 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 93 percent of the total population and (2) a CPI for Urban Wage Earners and Clerical Workers (CPI-W) which covers approximately 29 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 75 urban areas across the country from about 5,000 housing units and approximately 22,000 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-Naperville-Elgin, Ill.-Ind.-Wis., Core Based Statistical Area covered in this release is comprised of Cook, DeKalb, DuPage, Grundy, Kane, Kendall, Lake, McHenry, and Will Counties in Illinois; Jasper, Lake, Newton, 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.

Table 1. Consumer Price Index for All Urban Consumers (CPI-U): Indexes and percent changes for selected periods
Chicago-Naperville-Elgin, IL-IN-WI (1982-84=100 unless otherwise noted)

Item and Group	Indexes			Percent change from-
	Jul. 2018	Aug. 2018	Sep. 2018	Sep. 2017	Jul. 2018	Aug. 2018
Expenditure category
All items	237.870	238.098	238.957	1.6	0.5	0.4
All items (1967=100)	710.657	711.338	713.904	-	-	-
Food and beverages	248.655	247.499	250.270	2.2	0.6	1.1
Food	247.925	246.923	249.656	2.0	0.7	1.1
Food at home	234.113	232.336	235.910	0.4	0.8	1.5
Cereals and bakery products	262.078	258.303	263.597	-	0.6	2.0
Meats, poultry, fish and eggs	256.225	251.022	255.789	-	-0.2	1.9
Dairy and related products	209.072	206.805	210.062	-	0.5	1.6
Fruits and vegetables	300.063	303.333	302.492	-	0.8	-0.3
Nonalcoholic beverages and beverage materials(1)	187.921	188.900	191.872	-	2.1	1.6
Other food at home	189.727	187.449	191.907	-	1.1	2.4
Food away from home	262.199	262.199	263.823	4.0	0.6	0.6
Alcoholic beverages	257.659	254.068	257.417	3.8	-0.1	1.3
Housing	247.757	247.963	248.967	2.5	0.5	0.4
Shelter	313.263	312.873	314.012	3.0	0.2	0.4
Rent of primary residence(2)	330.920	331.771	332.746	2.6	0.6	0.3
Owners' equiv. rent of residences(2)(3)	319.277	319.919	320.777	3.8	0.5	0.3
Owners' equiv. rent of primary residence(2)(3)	319.277	319.919	320.777	3.8	0.5	0.3
Fuels and utilities	206.301	209.109	207.658	-0.1	0.7	-0.7
Household energy	161.383	164.232	162.580	-1.1	0.7	-1.0
Energy services(2)	164.557	167.465	165.760	-1.1	0.7	-1.0
Electricity(2)	160.005	161.872	159.483	-2.4	-0.3	-1.5
Utility (piped) gas service(2)	157.559	161.726	161.145	0.7	2.3	-0.4
Household furnishings and operations	89.010	89.460	91.209	0.5	2.5	2.0
Apparel	80.631	82.317	86.193	-6.4	6.9	4.7
Transportation	189.227	189.356	188.730	3.5	-0.3	-0.3
Private transportation	186.290	185.803	185.988	3.5	-0.2	0.1
New and used motor vehicles(4)	95.718	95.663	94.953	-	-0.8	-0.7
New vehicles(1)	170.462	171.057	170.329	-	-0.1	-0.4
Used cars and trucks(1)	270.340	270.646	257.907	-	-4.6	-4.7
Motor fuel	265.202	262.717	264.490	12.0	-0.3	0.7
Gasoline (all types)	262.555	260.091	261.826	12.0	-0.3	0.7
Gasoline, unleaded regular(5)	253.093	250.660	252.453	12.6	-0.3	0.7
Gasoline, unleaded midgrade(5)(6)	288.335	287.024	287.257	9.7	-0.4	0.1
Gasoline, unleaded premium(5)	285.744	283.028	284.229	9.0	-0.5	0.4
Motor vehicle insurance(1)	534.835	535.056	543.985	-	1.7	1.7
Medical care	505.584	506.753	505.523	0.9	0.0	-0.2
Recreation(4)	110.575	111.221	112.151	-2.6	1.4	0.8
Education and communication(4)	143.643	143.783	142.202	-0.6	-1.0	-1.1
Tuition, other school fees, and childcare(1)	1,192.035	1,197.070	1,167.483	-	-2.1	-2.5
Other goods and services	395.164	394.052	393.821	2.4	-0.3	-0.1
Commodity and service group
All items	237.870	238.098	238.957	1.6	0.5	0.4
Commodities	167.483	167.475	169.007	0.8	0.9	0.9
Commodities less food and beverages	126.795	127.173	128.167	-0.2	1.1	0.8
Nondurables less food and beverages	174.592	175.258	176.292	1.0	1.0	0.6
Durables	83.870	84.021	84.908	-1.7	1.2	1.1
Services	304.759	305.217	305.403	2.0	0.2	0.1
Special aggregate indexes
All items less medical care	226.379	226.565	227.517	1.7	0.5	0.4
All items less shelter	212.395	212.840	213.605	0.9	0.6	0.4
Commodities less food	131.373	131.678	132.734	0.0	1.0	0.8
Nondurables	212.371	212.232	214.075	1.7	0.8	0.9
Nondurables less food	180.139	180.621	181.770	1.3	0.9	0.6
Services less rent of shelter(3)	311.431	312.826	311.988	1.0	0.2	-0.3
Services less medical care services	290.264	290.733	290.899	2.1	0.2	0.1
Energy	202.665	203.169	203.019	5.8	0.2	-0.1
All items less energy	243.170	243.373	244.335	1.3	0.5	0.4
All items less food and energy	243.178	243.577	244.255	1.2	0.4	0.3
Footnotes (1) Index on a December 1977=100 base. (2) This index series was calculated using a Laspeyres estimator. All other item stratum index series were calculated using a geometric means estimator. (3) Index on a December 1982=100 base. (4) Indexes on a December 1997=100 base. (5) Special index based on a substantially smaller sample. (6) Index on a December 1993=100 base.
- Data not available. Note: Index applies to a month as a whole, not to any specific date. Data not seasonally adjusted.