The national OES survey is conducted semi-annually as part of a joint federal-state effort to gather occupational and wage data from employers. Establishments of all sizes, across all industries, and across all sectors of the economy are included. The purpose of the survey is to develop estimates of total wage and salary employment by occupation, wage range, and type of industry.
The sample of establishments surveyed is randomly selected and stratified by industry and employment size. This sampling method, combined with a process of "weighting" responses based on the number of similar establishments within a particular geographic area, ensures that all responses are equally important to the survey results. Generally, larger establishments represent only themselves in the estimating process and smaller establishments represent themselves and a number of similar firms.
Data collection is accomplished by the states using a structured and standardized survey form provided by the Bureau of Labor Statistics. Survey forms are mailed to employers during May and November of the survey year. Follow-up contacts to non-responding companies are made by mail, personal visit, and telephone and generally continue for a number of months after the initial survey form was mailed out.
The survey form asks for statistical information about the occupations and wage ranges of the employees working at a particular location for a specific time period. Explanatory information is included on the survey form to help employers determine where establishment jobs fit within the occupations specified on the survey forms and how to calculate hourly or annual wages.
The OES occupational classification structure is based on the U.S. Department of Commerce's Standard Occupational Classification (SOC) system. The SOC structure provides a unique code, title, and definition for each SOC occupation.
State occupational estimates are published each year by the individual states. National occupational estimates are published each year by BLS.
