Academic journal article
By Lettau, Michael K.; Zamora, Dee A.
Monthly Labor Review , Vol. 136, No. 8
Two statistical programs from the Bureau of Labor Statistics (BLS, the Bureau)--the National Compensation Survey (NCS) program and the Occupational Employment Statistics (OES) program --collect information about the hourly wage rates of workers by occupation. In the past, the calculation of the wage estimates from these programs has been largely separate, even though the resulting estimates can appear to measure essentially the same thing for a similar group of workers.
This article describes a procedure that combines data from the NCS and the OES survey to produce an experimental set of wage estimates by area, occupation, and job characteristic. Not only does the procedure make these wage estimates consistent with the wage information from both surveys, but it also has the potential to provide more extensive information about the wage rates of workers than either survey can provide individually.
OES estimates of mean hourly wages
The OES program produces employment and wage estimates for about 800 occupations. Estimates are available for the nation as a whole, for individual states, and for metropolitan and nonmetropolitan areas. (1) The BLS website offers further information about wage estimates available from the OES program.
NCS estimates of mean hourly earnings
Until 2011, the NCS program also produced estimates of annual and hourly earnings by occupation. These estimates were available for the nation as a whole, for the Census Bureau geographical divisions, and for metropolitan areas. (2) In addition, the NCS reported wage estimates broken down by job characteristic (full-time/part-time status, union/nonunion status, time-paid/incentive-paid status, and work level (3)). With the enactment of the 2011 federal budget, however, the sample size of the NCS was reduced and the program discontinued its publication of earnings estimates by occupation. Nonetheless, the data that supported these NCS wage estimates are still being collected, albeit with the reduced sample size, in order to support the compensation estimates from the Employment Cost Index/Employer Cost for Employee Compensation program and to continue to meet the requirements of the Federal Employees Pay Comparability Act of 1990. (4)
Combining OES and NCS data
One of the initial BLS goals in combining the NCS and OES data to produce wage estimates by area, occupation, and job characteristic was to avoid producing similar wage outputs separately. For example, the OES program reported the mean hourly wage as $17.18 for workers from protective service occupations in the Atlanta-Sandy Springs-Marietta Metropolitan Statistical Area (MSA) for May 2010, while the NCS program reported the mean hourly earnings as $16.98 for civilian workers in protective service occupations in the Atlanta-Sandy Springs-Gainesville Combined Statistical Area (CSA) for February 2010. (5) Two different wage estimates covering a similar group of workers has the potential to confuse users who are interested in wage information by area and occupation; by contrast, combining data from the two programs may provide BLS users with less confusing, higher quality information about wage rates, particularly if the combined estimates take advantage of the relative strengths of the two surveys: the large sample size of the OES survey and the data on job characteristics from the NCS. (6)
NCS-OES estimation method
The method for calculating wage estimates by job characteristic follows essentially the procedures and formula that the OES program uses to calculate its estimates for the mean hourly wage, with a step added to incorporate the information about job characteristics from the NCS. (7) The section titled "Occupational Employment Statistics," of the BLS Handbook of methods, describes the OES procedures in detail. In the OES survey, wage rates of workers are typically reported as grouped data across 12 consecutive, nonoverlapping wage intervals. …