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Handbook of Methods Occupational Employment and Wage Statistics History

Occupational Employment and Wage Statistics: History

Occupational Employment and Wage Statistics: History

Key developments

Hover over the red dot to see historical information.

  • 1977: OES data collection begins in every state and the District of Columbia
  • 1988: A new OES data collection method begins with the compilation of employment data by industry in a 3-year cycle
  • 1991: 15 states begin to collect wage information along with occupational employment information
  • 1996: OES program begins collecting occupational employment and wage data from an annual sample of 400,000 business establishments
  • 1997: First OES estimates published
  • 1999: OES switches to the Standard Occupational Classification (SOC) system
  • 2002: OES switches to the North American Industry Classification System (NAICS)
  • 2002: OES switches to semiannual data collection
  • 2003–04: OES publishes data semiannually
  • 2004: Estimates for residual (“all other”) occupations are published for the first time
  • 2005: OES returns to annual publication (but retains semiannual data collection)
  • 2005: OES adopts new metropolitan area definitions based on the 2000 decennial census
  • 2006: Estimates for nonmetropolitan areas are published for the first time
  • 2008: OES switches from the 2002 NAICS to the 2007 NAICS
  • 2009: National estimates by public/private sector ownership are added
  • 2010–2012: OES program transitions from the 2000 SOC to the 2010 SOC
  • 2012: OES switches from the 2007 NAICS to the 2012 NAICS
  • 2012: National estimates for SOC minor groups and broad occupations are added
  • 2014: Gambling establishments and casino hotels are reclassified in NAICS
  • 2015: OES adopts metropolitan area definitions based on the 2010 decennial census
  • 2017: OES aggregates some occupations and industries
  • 2017: Scope increased to cover some establishments previously classified in private households
  • 2017: OES switches from the 2012 NAICS to the 2017 NAICS
  • 2017–19: OES sample reduced
  • 2018: OES reduces some geographic detail
  • 2019: OES begins implementing the 2018 SOC
  • 2021: Name changed to Occupational Employment and Wage Statistics (OEWS)

The OEWS program in its current form dates to 1996 and began publishing occupational employment and wage estimates in 1997. Since 1997, the OEWS data have undergone a number of changes, including changes to the occupational and industry classification systems used, changes to the metropolitan and nonmetropolitan area definitions, and changes to the sample size and survey reference dates.

Changes in occupational classification

The 1997 and 1998 OEWS estimates used an occupational classification system that was specific to the OEWS program. In 1999, the OEWS program adopted the federal Standard Occupational Classification (SOC) system. The 1999–May 2009 estimates are based on the 2000 version of the SOC.

Between May 2010 and May 2012, the OEWS program transitioned to the 2010 SOC. Because each set of OEWS estimates is produced by combining three years of survey data, the May 2010 and May 2011 estimates were based on a combination of newer survey panels collected using the 2010 SOC and older survey panels collected using the 2000 SOC. Therefore, these estimates used a hybrid of the 2000 and 2010 systems that included some OEWS-specific combinations of occupations. The May 2012 estimates were the first set of estimates based fully on the 2010 SOC. More information about the hybrid system used in the May 2010 and May 2011 estimates is available in the OEWS frequently asked questions.

Beginning with the May 2017 estimates, the OEWS program replaced 21 SOC detailed occupations with SOC broad occupations or OEWS-specific combinations of detailed occupations. These changes were made to improve data quality in cases where occupations are similar and it is difficult to obtain the information needed to code accurately to the detailed occupational level. More information about these aggregations is available at

The OEWS program began implementing the 2018 SOC with the May 2019 estimates. Because of the OEWS 3-year methodology, the May 2019 and May 2020 estimates use a hybrid of the 2010 and 2018 SOCs that includes some combinations of occupations that are not found in either version of the system. The May 2021 estimates will be the first estimates based entirely on survey data collected using the 2018 SOC. More information on the hybrid classification system used in the May 2019 and May 2020 estimates is available on the OEWS 2018 SOC implementation page and in the frequently asked questions.

The May 2019 estimates also introduced some new occupational aggregations designed to improve data quality, along with changes to some of the occupational aggregations introduced in May 2017.

Changes in industry classification and survey scope

The 1997–2001 OEWS estimates used the Standard Industrial Classification (SIC) system. In 2002, the OEWS program switched from the SIC to the 2002 North American Industry Classification System (NAICS). Updates to the NAICS system were adopted in the May 2008 estimates (2007 NAICS), May 2012 estimates (2012 NAICS), and May 2017 estimates (2017 NAICS).

Beginning with the May 2014 estimates, gambling establishments and casino hotels owned by local governments were moved from the OEWS local government industry (9993) to NAICS 7132 Gambling Industries and 72112 Casino Hotels, respectively.

The May 2017 estimates included for the first time some establishments that were reclassified from NAICS 814 Private Households, which is out of scope for the OEWS survey, to NAICS 624120 Services for the Elderly and Persons with Disabilities, which is in scope. As a result, the May 2017 estimates may show increased employment in occupations that are common in NAICS 624120.

Changes to area definitions

The OEWS program uses standard metropolitan area definitions from the U.S. Office of Management and Budget (OMB). For the New England states, OEWS uses the New England City and Town Area (NECTA) definitions rather than the Metropolitan Statistical Area (MSA) definitions. The OEWS nonmetropolitan areas use definitions that are specific to the OEWS program and are developed in cooperation with the state workforce agencies.

The OEWS program implemented major revisions to the area definitions in the May 2005 and May 2015 estimates. The May 2005 estimates introduced revised OMB area definitions based on the results of the 2000 decennial census. The May 2015 estimates introduced revised definitions based on the 2010 census. In addition to the major revisions in May 2005 and May 2015, smaller revisions were implemented in other years. Because the OEWS nonmetropolitan areas cover the remainder of each state outside of the OMB-defined metropolitan areas, changes to the metropolitan area definitions may also affect the nonmetropolitan area definitions.

With the May 2018 estimates, the OEWS program reduced the level of geographic detail available in some areas. For the 11 large metropolitan areas that are further broken down into metropolitan divisions, OEWS no longer publishes data for the divisions. Data for these 11 areas are now available at the Metropolitan Statistical Area (MSA) or New England City and Town Area (NECTA) level only. In addition, some smaller nonmetropolitan areas were combined to form larger nonmetropolitan areas. More information on these area changes is available at

Changes to sample size and reference period

Before 2002, the OEWS program collected data from 400,000 business establishments annually with a 4⁠th quarter reference date. Survey respondents were asked to provide data as of an October, November, or December payroll, depending on the specific respondent.

In 2002, OEWS switched to semiannual data collection to reduce seasonal effects. Data were collected in two semiannual survey panels of approximately 200,000 business establishments each, with reference dates of May 12 and November 12.

The OEWS program also published estimates semiannually in 2003 and 2004. In 2005, the OEWS program returned to publishing data annually, but retained semiannual data collection.

The OEWS sample has been reduced in recent survey panels. The May 2020 and November 2019 OEWS survey panels each had a sample of approximately 180,000 establishments. The May 2019 OEWS survey panel had a sample of approximately 183,000 establishments. The November 2017, May 2018, and November 2018 survey panels each had a sample of approximately 186,000 establishments.

Program name change

In the spring of 2021, the Occupational Employment Statistics (OES) program began using the name Occupational Employment and Wage Statistics (OEWS) to better reflect the range of data available from the program. Data released on or after March 31, 2021, will reflect the new program name. Data collection materials, including forms, emails, and letters, will be updated for employers in the May 2021 survey panel. Webpages, publications, and other materials associated with previous data releases will retain the Occupational Employment Statistics name.

Data before 1997

Data from the immediate predecessor to the current OEWS program are available at the bottom of the main OEWS data page. These data cover the period 1988–95 and are not directly comparable to more recent OEWS data. The 1988–95 data consist only of national occupational employment estimates by 2- and 3-digit SIC industry, with data for each industry available only once every three years. These estimates do not contain wage data or state and area data. Because data are not available for all industries in a given year, it is not possible to calculate total national employment in an occupation from these estimates.



Last Modified Date: March 31, 2021