U.S. Bureau of Labor Statistics
Employment Cost Index technical note
Last Modified Date: January 31, 2014
The Employment Cost Index (ECI) measures the change in the cost of labor, free from the influence of
employment shifts among occupations and industries. Detailed information on survey concepts,
coverage, and methods can be found in BLS Handbook of Methods, Chapter 8, National Compensation
Measures, Bureau of Labor Statistics, on the Internet at www.bls.gov/opub/hom/pdf/homch8.pdf.
Data for the December 2013 reference period were collected from a probability sample of approximately
44,200 occupational observations selected from a sample of about 9,100 establishments in private
industry and approximately 9,100 occupations from a sample of about 1,400 establishments in state and
Health insurance data
Data from the ECI that provide 12-month percent changes in employer costs for health insurance in
private industry are available at www.bls.gov/ect/sp/echealth.pdf.
Historical listings that provide all ECI data are available at www.bls.gov/ect/#tables. Included among
these listings is one that provides continuous occupational and industry series. This listing uses the
Standard Industrial Classification Manual and Census of Population series through 2005 and the North
American Industry Classification System and Standard Occupational Classification from 2006 to the
present. It provides the official series from the beginning of the ECI in 1975 through the current quarter.
For more information on the criteria used in defining continuous series, see the article published in the
Monthly Labor Review at www.bls.gov/opub/mlr/2006/04/art2full.pdf.
Employer Costs for Employee Compensation data
The costs per hour worked of compensation components, based on data from the ECI, are published in a
separate news release titled "Employer Costs for Employee Compensation" (ECEC). The next ECEC
release is scheduled for 10:00 a.m. (EDT), Wednesday, March 12, 2014. Historical ECEC data are
available in summary documents at www.bls.gov/ect/#tables. Since the ECEC is calculated with current
employment weights rather than the fixed weights used in computing the ECI, year-to-year changes in
the cost levels usually differ from those in the ECI.
Updated employment weights and methodology changes
Fixed employment weights are used each quarter to calculate aggregate indexes for civilian, private, and
state and local government. These fixed weights are also used to derive all of the industry and
occupation series indexes. Beginning in December 2013, the 2012 employment counts from the
Bureaus Occupational Employment Survey were used. Additional methodology changes include a
partial implementation of the new NCS national sample design and adjustments to aggregate seasonally
adjusted series. For more information, please contact the National Compensation Survey at 202-691-
6199 or NCSinfo@bls.gov.