Technical Note
Scope of the survey
The Occupational Employment and Wage Statistics (OEWS) survey is a semiannual survey
measuring occupational employment and wage rates for wage and salary workers in
nonfarm establishments in the United States. The OEWS data available from BLS include
cross-industry occupational employment and wage estimates for the nation; over 580
areas, including states and the District of Columbia, metropolitan statistical areas
(MSAs), nonmetropolitan areas, and territories; national industry-specific estimates
at the NAICS sector, 3-digit, most 4-digit, and selected 5- and 6-digit industry
levels; and national estimates by ownership across all industries and for schools
and hospitals.
The OEWS survey is a cooperative effort between BLS and the State Workforce Agencies
(SWAs). BLS funds the survey and provides the procedures and technical support, while
the SWAs collect most of the data. OEWS estimates are constructed from a sample of
about 1.1 million establishments. Each year, two semiannual panels of approximately
179,000 to 187,000 sampled establishments are contacted, one panel in May and the
other in November. Responses are obtained by Internet or other electronic means, mail,
email, telephone, or personal visit. The May 2021 estimates are based on responses
from six semiannual panels collected over a 3-year period: May 2021, November 2020,
May 2020, November 2019, May 2019, and November 2018. The unweighted sampled
employment of 82 million across all six semiannual panels represents approximately 62
percent of total national employment. The overall national response rate for the six
panels, based on the 50 states and the District of Columbia, is 67.2 percent based on
establishments and 64.5 percent based on weighted sampled employment.
The occupational coding system
The May 2021 OEWS estimates contain approximately 830 occupational categories based
on the Office of Management and Budget's 2018 Standard Occupational Classification
(SOC) system. Together, these occupations make up 22 of the 23 SOC major occupational
groups. Major group 55, Military Specific Occupations, is not included.
For more information about the SOC system, please see the BLS website at www.bls.gov/soc/.
The industry coding system
The May 2021 OEWS estimates use the 2017 North American Industry Classification System
(NAICS). For more information about NAICS, see the BLS website at
www.bls.gov/bls/naics.htm.
The OEWS survey excludes the majority of the agricultural sector, with the exception of
logging (NAICS 113310), support activities for crop production (NAICS 1151), and
support activities for animal production (NAICS 1152). Private households (NAICS 814)
also are excluded. OEWS federal government data include the U.S. Postal Service and
the federal executive branch only. All other industries, including state and local
government, are covered by the survey.
Survey sample
The OEWS survey draws its sample from state unemployment insurance (UI) files.
Supplemental sources are used for rail transportation (NAICS 4821) and Guam because
they do not report to the UI program. The OEWS survey sample is stratified by
metropolitan and nonmetropolitan area, industry, and size.
To provide the most occupational coverage, larger employers are more likely to be
selected than smaller employers. A census is taken of the executive branch of the
federal government, the U.S. Postal Service, and state government.
Concepts
Occupational employment is the estimate of total wage and salary employment in an
occupation. The OEWS survey defines employment as the number of workers who can be
classified as full- or part-time employees, including workers on paid vacations or
other types of paid leave; workers on unpaid short-term absences; salaried officers,
executives, and staff members of incorporated firms; employees temporarily assigned
to other units; and employees for whom the reporting unit is their permanent duty
station, regardless of whether that unit prepares their paycheck. The survey does not
include the self-employed, owners and partners in unincorporated firms, household
workers, or unpaid family workers.
Wages for the OEWS survey are straight-time, gross pay, exclusive of premium pay.
Base rate; cost-of-living allowances; guaranteed pay; hazardous-duty pay; incentive
pay, including commissions and production bonuses; and tips are included. Excluded
are overtime pay, severance pay, shift differentials, nonproduction bonuses, employer
cost for supplementary benefits, and tuition reimbursements.
The responding establishments are instructed to report hourly rates for part-time
workers and to report annual rates for occupations that are typically paid at an
annual rate but do not work 2,080 hours per year, such as teachers, pilots, and
flight attendants. Other workers, such as some entertainment workers, are paid
hourly rates, but generally do not work 40 hours per week, year round. For these
workers, only an hourly wage is reported.
OEWS receives wage rate data for the federal government, the U.S. Postal Service,
most state governments, and some local government and private sector establishments.
For the remaining establishments, the OEWS survey data were placed into 12 intervals.
The intervals are defined both as hourly rates and the corresponding annual rates,
where the annual rate for an occupation is calculated by multiplying the hourly wage
rate by a typical work year of 2,080 hours.
Estimation methodology
The OEWS survey is designed to produce estimates by combining six panels of data
collected over a 3-year period. Each OEWS panel contains approximately 179,000 to
187,000 establishments. The full six-panel sample of 1.1 million establishments
allows the production of estimates at detailed levels of geography, industry, and
occupation.
The May 2021 estimates were produced by a model-based estimation method using three
years of OEWS data (MB3). Under MB3, data provided by survey respondents are used to
model occupational staffing patterns and wages for all unobserved establishments in
the population, including establishments that were not sampled, sampled
establishments that did not respond, and respondents that did not meet stability
criteria.
A donor pool typically consisting of 10 nearest neighbor responding establishments
is used to predict data for each unobserved establishment; if 10 donors are not
available, then as few as 5 can be used. Donors are matched to recipients based on
detailed industry, geographic area, ownership, size, and survey panel. Within a
given donor pool, donors that are more similar to the unobserved establishment are
given more weight in determining the modeled data.
Each establishment's population employment is set as the average of its May 2021 and
November 2020 employment from the Quarterly Census of Employment and Wages, the UI
database from which the OEWS sample is drawn. Using adjustment factors derived from
the OEWS survey data, wages collected in earlier survey panels are adjusted to the
reference date of the estimates and donor wages are adjusted for differences between
donor and recipient characteristics such as geographic area and industry.
Changes and special procedures in the May 2021 estimates
With the May 2021 estimates, the OEWS program has implemented a new estimation
method. This new model-based method, called MB3, has advantages over the previous
estimation method, as described in the Monthly Labor Review article at
www.bls.gov/opub/mlr/2019/article/model-based-estimates-for-the-occupational-
employment-statistics-program.htm. For more information, see the May 2021 Survey
Methods and Reliability Statement at www.bls.gov/oes/methods_21.pdf.
The May 2021 estimates are the first OEWS estimates based entirely on survey data
collected using the 2018 SOC. The May 2019 and May 2020 estimates were based on a
combination of survey data collected using the 2010 SOC and survey data collected
using the 2018 SOC and used a hybrid of the two classification systems. See
www.bls.gov/soc/2018 and www.bls.gov/oes/oes_ques.htm#qf10 for more information.
May 2021 OEWS data are available for most 2018 SOC detailed occupations. To improve
data quality, the OEWS program has replaced some 2018 SOC detailed occupations with
SOC broad occupations or OEWS-specific aggregations.
The May 2021 OEWS estimates use the metropolitan area definitions delineated in
Office of Management and Budget (OMB) Bulletin 17-01. For more information, please
see www.bls.gov/oes/current/msa_def.htm.
Response rates for the May 2021 estimates were negatively affected by the difficulty
of collecting data from employers during the COVID-19 pandemic. Lower response rates
may negatively affect data availability and data quality.
For more information
Answers to frequently asked questions about the OEWS data are available at
www.bls.gov/oes/oes_ques.htm. If you are deaf, hard of hearing, or have a speech
disability, please dial 7-1-1 to access telecommunications relay services.
United States Department of Labor
