TECHNICAL NOTE

Employer Costs for Employee Compensation (ECEC), a product of the National Compensation Survey, 
measures the average cost to employers for wages and salaries and benefits per employee hour worked. The 
ECEC includes the civilian economy, which includes data from both private industry and state and local 
government. Excluded from private industry are the self-employed and farm and private household workers. 
Federal government workers are excluded from the public sector. The private industry series and the state 
and local government series provide data for the two sectors separately. All workers are included in the 
benefit cost estimates including those that do not have plan access or do not participate. Costs are also 
affected by other factors such as cost sharing between employers and employees, plan features, and plan 
generosity.

Sample size
Data for the December 2018 reference period were collected from a probability sample of approximately 
27,000 occupational observations selected from a sample of about 6,500 private industry establishments 
and approximately 8,000 occupational observations selected from a sample of about 1,400 state and local 
government establishments that provided data at the initial interview.  

Measures of reliability
Relative standard errors for all estimates in the most recent news release are available at 
www.bls.gov/web/ecec/ececrse.txt. Footnotes have been added for estimates with relative standard errors 
greater than 30 percent. For more information on standard errors, see “Measuring Trends in the Structure and 
Levels of Employer Costs for Employee Compensation,” at www.bls.gov/opub/mlr/cwc/measuring-trends-in-the-
structure-and-levels-of-employer-costs-for-employee-compensation.pdf.

Benchmarking by establishment size and industry
For information on benchmarking by establishment size and industry, see “The Weighting Process Used in the 
Employer Costs for Employee Compensation Series for the National Compensation Survey,” at 
www.bls.gov/osmr/pdf/st110220.pdf.

Comparing private and public sector data
Compensation cost levels in state and local government should not be directly compared with levels in private 
industry. Differences between these sectors stem from factors such as variation in work activities and 
occupational structures. Manufacturing and sales, for example, make up a large part of private industry work 
activities but are rare in state and local government. Professional and administrative support occupations 
(including teachers) account for two-thirds of the state and local government workforce, compared with 
one-half of private industry.

Quarterly publication focus
This quarter’s release focuses on supplemental pay benefit costs in private industry. Topics of news releases 
for the upcoming reference periods are as follows:
•  March 2019—Compensation costs by wage percentile, and 15 metropolitan areas, as well as health benefit 
costs in private industry
•  June 2019—Retirement and savings benefit costs in private industry

Additional information
The “National Compensation Measures,” in the BLS Handbook of Methods at www.bls.gov/opub/hom/ncs/home.htm 
provides explanations of survey design, estimation methodology and additional resources. For data on the 
percentage of workers with access to and participating in employer-sponsored benefit plans such as health 
care, see www.bls.gov/ebs.