Transmission of material in this release is embargoed until
8:30 a.m. (EDT) Tuesday, June 18, 2013 USDL-13-1175
Technical information: (202) 691-7000 Reed.Steve@bls.gov www.bls.gov/cpi
Media Contact: (202) 691-5902 PressOffice@bls.gov
Consumer Price Index - May 2013
The Consumer Price Index for All Urban Consumers (CPI-U) increased
0.1 percent in May on a seasonally adjusted basis, the U.S. Bureau of
Labor Statistics reported today. Over the last 12 months, the all
items index increased 1.4 percent before seasonal adjustment.
The shelter index rose 0.3 percent and accounted for more than half
of the seasonally adjusted all items increase in May. The energy
index rose modestly, with the gasoline index flat but increases in
the electricity and natural gas indexes accounting for the rise. The
food index, however, turned down in May, with the food at home index
falling 0.3 percent.
The index for all items less food and energy increased 0.2 percent in
May. Besides the shelter increase, advances in the indexes for
airline fares, recreation, and apparel also contributed to the rise.
In contrast, the indexes for medical care and used cars and trucks
declined in May.
The all items index increased 1.4 percent over the last 12 months, an
increase from last month's 1.1 percent figure. The 12-month change in
the index for all items less food and energy remained at 1.7 percent.
The food index has risen modestly over the last 12 months, advancing
1.4 percent, while the index for energy has declined, falling 1.0
Table A. Percent changes in CPI for All Urban Consumers (CPI-U): U.S. city
Seasonally adjusted changes from
Nov. Dec. Jan. Feb. Mar. Apr. May 12-mos.
2012 2012 2013 2013 2013 2013 2013 ended
All items.................. -.2 .0 .0 .7 -.2 -.4 .1 1.4
Food...................... .2 .2 .0 .1 .0 .2 -.1 1.4
Food at home............. .3 .2 .0 .1 -.1 .1 -.3 .8
Food away from home (1).. .1 .1 .1 .1 .2 .3 .2 2.3
Energy.................... -3.4 -.8 -1.7 5.4 -2.6 -4.3 .4 -1.0
Energy commodities....... -5.7 -1.5 -3.0 8.6 -4.1 -7.9 -.1 -4.2
Gasoline (all types).... -6.0 -1.9 -3.0 9.1 -4.4 -8.1 .0 -4.1
Fuel oil (1)............ -.2 .0 -.2 3.1 -2.1 -4.4 -2.9 -5.8
Energy services.......... .6 .3 .4 .5 -.2 1.4 1.2 4.5
Electricity............. .4 .2 1.1 .3 -.6 .5 .8 1.7
Utility (piped) gas
service.............. 1.5 .7 -1.7 1.2 1.0 4.4 2.4 14.2
All items less food and
energy................. .1 .1 .3 .2 .1 .1 .2 1.7
Commodities less food and
energy commodities.... -.1 -.1 .2 .0 -.1 .0 .0 -.2
New vehicles............ .3 .2 .1 -.3 .1 .3 .0 1.1
Used cars and trucks.... -.4 -.3 .2 .8 1.2 .6 -.1 -1.6
Apparel................. -.5 .1 .8 -.1 -1.0 -.3 .2 .2
Medical care commodities -.3 -.3 .1 -.4 .1 .1 -.5 .0
Services less energy
services.............. .2 .2 .3 .2 .2 .1 .2 2.3
Shelter................. .2 .1 .2 .2 .2 .2 .3 2.3
Transportation services .2 .4 .5 .1 .2 -.2 .4 2.6
Medical care services... .3 .3 .2 .3 .3 -.1 .0 2.9
1 Not seasonally adjusted.
Consumer Price Index Data for May 2013
The food index fell 0.1 percent in May after rising 0.2 percent in
April. The index for food at home fell 0.3 percent, its largest
decline since July 2009. Four of the six major grocery store food
group indexes posted declines, led by nonalcoholic beverages, which
fell 1.1 percent. The index for dairy and related products decreased
0.8 percent, its third decline in the last four months. The indexes
for cereals and bakery products and other food at home both turned
down in May, falling 0.4 percent and 0.3 percent, respectively. The
index for meats, poultry, fish, and eggs, which increased in April,
was unchanged in May. The only grocery store food group index to rise
was fruits and vegetables, which increased 0.4 percent in May after a
1.4 percent decline in April. The food at home index has increased
0.8 percent over the past year; the fruits and vegetables index has
risen the most of the six groups over that span, increasing 2.1
percent. The index for food away from home rose 0.2 percent in May
and has risen 2.3 percent over the past year.
The energy index rose in May, increasing 0.4 percent after
substantial declines in March and April. The gasoline index, which
declined sharply the previous two months, was unchanged in May.
(Before seasonal adjustment, gasoline prices rose 0.8 percent in
May.) The fuel oil index continued to fall; its 2.9 percent decrease
in May was its third consecutive decline. However, other energy
indexes rose. The electricity index, which increased 0.5 percent in
April, rose 0.8 percent in May. The natural gas index rose 2.4
percent, its fourth consecutive increase. Over the last 12 months
energy indexes are mixed, with the index for fuel oil falling 5.8
percent and the gasoline index down 4.1 percent, but the natural gas
index rising 14.2 percent and the electricity index up 1.7 percent.
All items less food and energy
The index for all items less food and energy increased 0.2 percent in
May after rising 0.1 percent in both March and April. The shelter
index rose 0.3 percent in May, its largest increase since July 2011.
The index for rent rose 0.3 percent and the index for owners'
equivalent rent increased 0.2 percent. The index for lodging away
from home rose 1.2 percent in May, its fifth consecutive increase.
Besides shelter, several other indexes also increased in May. The
index for airline fares rose 2.2 percent after declining in April.
The indexes for apparel and recreation both rose 0.2 percent after
declining in recent months. In contrast to these increases, the index
for medical care declined in May, falling 0.1 percent. The index for
medical care services was unchanged while the index for medical care
commodities fell 0.5 percent, with the index for prescription drugs
decreasing 0.6 percent. The index for used cars and trucks also
declined, falling 0.1 percent after increasing in each of the first
four months of the year. Several indexes were unchanged in May,
including new vehicles, tobacco, and household furnishings and
The index for all items less food and energy increased 1.7 percent
for the 12 months ending May. The index for shelter has risen 2.3
percent over the last 12 months. The medical care index has risen 2.2
percent, its smallest 12-month increase since September 1972. The
index for medical care services has increased 2.9 percent over the
last year, while the index for medical care commodities was
unchanged, with the prescription drug index down 0.1 percent over the
Not seasonally adjusted CPI measures
The Consumer Price Index for All Urban Consumers (CPI-U) increased
1.4 percent over the last 12 months to an index level of 232.945
(1982-84=100). For the month, the index increased 0.2 percent prior
to seasonal adjustment.
The Consumer Price Index for Urban Wage Earners and Clerical Workers
(CPI-W) increased 1.2 percent over the last 12 months to an index
level of 229.399 (1982-84=100). For the month, the index increased
0.2 percent prior to seasonal adjustment.
The Chained Consumer Price Index for All Urban Consumers (C-CPI-U)
increased 1.3 percent over the last 12 months. For the month, the
index increased 0.2 percent on a not seasonally adjusted basis.
Please note that the indexes for the post-2011 period are subject to
The Consumer Price Index for June 2013 is scheduled to be released on
Tuesday, July 16, 2013, at 8:30 a.m. (EDT).
Discontinuation of Department Store Inventory Indexes
The Bureau of Labor Statistics will discontinue publication of its
Department Store Inventory indexes after the release of the December
2013 CPI in mid-January 2014, and these values will no longer be
uploaded to the Labstat database. For further information please
contact Sharon Gibson at 202-691-6968 or firstname.lastname@example.org.
Publication Changes for Average Price Series
The Bureau of Labor Statistics will discontinue publication of three
average price series after the release of the June 2013 CPI in mid-
July 2013. They are:
- utility (piped) gas, 40 therms;
- utility (piped) gas, 100 therms; and
- electricity, 500 kilowatt hours.
The Bureau will, however, continue to publish average prices for
utility (piped) gas on a per therm basis, and will continue to
publish electricity prices on a per kilowatt hour basis. As such,
users will be able to convert these data to any consumption amount.
CPI Detailed Report table P1. Average residential prices for utility
(piped) gas, electricity, and fuel oil, U.S. city average and
selected areas will no longer be published. Data for fuel oil #2,
per gallon (3.785 liters) will continue to be available in the CPI
Average Price Data public database.
Facilities for Sensory Impaired
Information from this release will be made available to sensory
impaired individuals upon request. Voice phone: 202-691-5200,
Federal Relay Services: 1-800-877-8339.
Brief Explanation of the CPI
The Consumer Price Index (CPI) is a measure of the average change in
prices over time of goods and services purchased by households. The
Bureau of Labor Statistics publishes CPIs for two population groups:
(1) the CPI for Urban Wage Earners and Clerical Workers (CPI-W),
which covers households of wage earners and clerical workers that
comprise approximately 29 percent of the total population and (2) the
CPI for All Urban Consumers (CPI-U) and the Chained CPI for All Urban
Consumers (C-CPI-U), which cover approximately 88 percent of the
total population and include in addition to wage earners and clerical
worker households, 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 CPIs are based on prices of food, clothing, shelter, and fuels,
transportation fares, charges for doctors' and dentists' services,
drugs, and other goods and services that people buy for day-to-day
living. Prices are collected each month in 87 urban areas across the
country from about 4,000 housing units and approximately 26,000
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. Prices of fuels and a few
other items are obtained every month in all 87 locations. Prices of
most other commodities and services are collected every month in the
three largest geographic areas and every other month in other areas.
Prices of most goods and services are obtained by personal visits or
telephone calls of the Bureau's trained representatives.
In calculating the index, price changes for the various items in each
location are averaged together with weights, which represent their
importance in the spending of the appropriate population group.
Local data are then combined to obtain a U.S. city average. For the
CPI-U and CPI-W separate indexes are also published by size of city,
by region of the country, for cross-classifications of regions and
population-size classes, and for 27 local areas. Area indexes do not
measure differences in the level of prices among cities; they only
measure the average change in prices for each area since the base
period. For the C-CPI-U data are issued only at the national level.
It is important to note that the CPI-U and CPI-W are considered final
when released, but the C-CPI-U is issued in preliminary form and
subject to two annual revisions.
The index measures price change from a designed reference date. For
the CPI-U and the CPI-W the reference base is 1982-84 equals 100.
The reference base for the C-CPI-U is December 1999 equals 100. An
increase of 16.5 percent from the reference base, for example, is
shown as 116.500. 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 visit the CPI home page on the Internet at
http://www.bls.gov/cpi/ or contact our CPI Information and Analysis
Section on (202) 691-7000.
Note on Sampling Error in the Consumer Price Index
The CPI is a statistical estimate that is subject to sampling error
because it is based upon a sample of retail prices and not the
complete universe of all prices. BLS calculates and publishes
estimates of the 1-month, 2-month, 6-month and 12-month percent
change standard errors annually, for the CPI-U. These standard error
estimates can be used to construct confidence intervals for
hypothesis testing. For example, the estimated standard error of the
1 month percent change is 0.04 percent for the U.S. All Items
Consumer Price Index. This means that if we repeatedly sample from
the universe of all retail prices using the same methodology, and
estimate a percentage change for each sample, then 95% of these
estimates would be within 0.08 percent of the 1 month percentage
change based on all retail prices. For example, for a 1-month change
of 0.2 percent in the All Items CPI for All Urban Consumers, we are
95 percent confident that the actual percent change based on all
retail prices would fall between 0.12 and 0.28 percent. For the
latest data, including information on how to use the estimates of
standard error, see "Variance Estimates for Price Changes in the
Consumer Price Index, January-December 2012". These data are
available on the CPI home page (http://www.bls.gov/cpi), or by using
the following link: http://www.bls.gov/cpi/cpivar2012.pdf
Calculating Index Changes
Movements of the indexes from one month to another are usually
expressed as percent changes rather than changes in index points,
because index point changes are affected by the level of the index in
relation to its base period while percent changes are not. The
example below illustrates the computation of index point and percent
Percent changes for 3-month and 6-month periods are expressed as
annual rates and are computed according to the standard formula for
compound growth rates. These data indicate what the percent change
would be if the current rate were maintained for a 12-month period.
Index Point Change
Less previous index
Equals index point change
Index point difference
Divided by the previous index
Results multiplied by one hundred
Equals percent change
A Note on Seasonally Adjusted and Unadjusted Data
Because price data are used for different purposes by different
groups, the Bureau of Labor Statistics publishes seasonally adjusted
as well as unadjusted changes each month.
For analyzing general price trends in the economy, seasonally
adjusted changes are usually preferred since they eliminate the
effect of changes that normally occur at the same time and in about
the same magnitude every year--such as price movements resulting from
changing climatic conditions, production cycles, model changeovers,
holidays, and sales.
The unadjusted data are of primary interest to consumers concerned
about the prices they actually pay. Unadjusted data also are used
extensively for escalation purposes. Many collective bargaining
contract agreements and pension plans, for example, tie compensation
changes to the Consumer Price Index before adjustment for seasonal
Seasonal factors used in computing the seasonally adjusted indexes
are derived by the X-12-ARIMA Seasonal Adjustment Method. Seasonally
adjusted indexes and seasonal factors are computed annually. Each
year, the last 5 years of seasonally adjusted data are revised. Data
from January 2008 through December 2012 were replaced in January
2013. Exceptions to the usual revision schedule were: the updated
seasonal data at the end of 1977 replaced data from 1967 through
1977; and, in January 2002, dependently seasonally adjusted series
were revised for January 1987-December 2001 as a result of a change
in the aggregation weights for dependently adjusted series. For
further information, please see "Aggregation of Dependently Adjusted
Seasonally Adjusted Series," in the October 2001 issue of the CPI
Effective with the publication of data from January 2006 through
December 2010 in January 2011, the Video and audio series and the
Information technology, hardware and services series were changed
from independently adjusted to dependently adjusted. This resulted
in an increase in the number of seasonal components used in deriving
seasonal movement of the All items and 54 other lower level
aggregations, from 73 for the publication of January 1998 through
December 2005 data to 82 for the publication of seasonally adjusted
data for January 2006 and later. Each year the seasonal status of
every series is reevaluated based upon certain statistical criteria.
If any of the 82 components change their seasonal adjustment status
from seasonally adjusted to not seasonally adjusted, not seasonally
adjusted data will be used in the aggregation of the dependent series
for the last 5 years, but the seasonally adjusted indexes before that
period will not be changed. Note: 37 of the 82 components are not
seasonally adjusted for 2013.
Seasonally adjusted data, including the all items index levels, are
subject to revision for up to five years after their original
release. For this reason, BLS advises against the use of these data
in escalation agreements.
Effective with the calculation of the seasonal factors for 1990, the
Bureau of Labor Statistics has used an enhanced seasonal adjustment
procedure called Intervention Analysis Seasonal Adjustment for some
CPI series. Intervention Analysis Seasonal Adjustment allows for
better estimates of seasonally adjusted data. Extreme values and/or
sharp movements which might distort the seasonal pattern are
estimated and removed from the data prior to calculation of seasonal
factors. Beginning with the calculation of seasonal factors for
1996, X-12-ARIMA software was used for Intervention Analysis Seasonal
For the seasonal factors introduced in January 2013, BLS adjusted 31
series using Intervention Analysis Seasonal Adjustment, including
selected food and beverage items, motor fuels, electricity and
vehicles. For example, this procedure was used for the Motor fuel
series to offset the effects of events such as damage to oil
refineries from Hurricane Katrina.
For a complete list of Intervention Analysis Seasonal Adjustment
series and explanations, please refer to the article "Intervention
Analysis Seasonal Adjustment", located on our website at
For additional information on seasonal adjustment in the CPI, please
write to the Bureau of Labor Statistics, Division of Consumer Prices
and Price Indexes, Washington, DC 20212 or contact Chris Graci at
(202) 691-5826, or by e-mail at email@example.com or contact
Carlyle Jackson at (202) 691-6984, or by e-mail at
firstname.lastname@example.org . If you have general questions about the
CPI, please call our information staff at (202) 691-7000.