26. November 2012 09:49
ERI continually reviews Occupational Employment Statistics (OES) data, a survey collected via a headcount of individuals within an occupational family and then converted into salary estimates. Recently, local OES “All Occupations” averages appear overstated.
When the Bureau of Labor Statistics (BLS) presents the results of the OES survey, they report by Standard Occupational Classification (SOC) codes, and they include both Major Occupational Groups and the six-digit SOC code. Looking at the actual data collection tool, there are only check boxes for the six-digit SOC groups. (The OES is not a salary survey in the sense that it records actual salaries – the questionnaire merely provides ranges for employers to record how many incumbents they have in a range for a particular SOC.)
One might assume that the Major Groups are just the average of the SOC codes that fall in that Major Group weighted by the incumbent counts in each group. But some simple analyses can show inconsistencies with that assumption.
For this analysis, we compared the weighted averages of all of the six-digit SOC salaries (which would cover all occupations) for each Metropolitan Statistical Areas (MSA) to the corresponding reported “All Occupation” average (Major Group 0). For the 462 MSAs, 75% reported an “All Occupation” average greater than 101% of the calculated average from all occupations. Twenty-two percent of the MSAs were between 100% and 101%, whereas only 15 (3%) reported an “All Occupation” average less than the calculated average. Because these are overall averages rather than within-SOC averages, one would expect a more symmetric distribution around 100.
While it is convenient to use the Major Group averages (including the “All Occupation” average), these results should be interpreted with caution. It is also noteworthy to mention that, for prevailing wage determination purposes, the Major Groups cannot be used. So, if the Major Group averages appear overstated, they would not impact wage determinations for visa purposes.
Data are from the most recent OES survey (http://www.bls.gov/oes/).
Table 1. Count of MSAs by Ratio of Reported “All Occupation” Average to Calculated Average