Employment Cost Index technical note
TECHNICAL NOTE
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.
Sample size
Data for the March 2012 reference period were collected from a probability sample of
approximately 47,900 occupational observations selected from a sample of about 9,600 establishments in
private industry and approximately 9,300 occupations from a sample of about 1,400 establishments in
state and local governments.
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
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), Thursday, June 7, 2012. 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.
Last Modified Date: April 27, 2012
