All data is available not seasonally adjusted, and some data is available seasonally adjusted.
What is seasonal adjustment?
Seasonal adjustment is a process whereby the normal seasonal changes are removed or discounted from monthly data. For example, we know that some industries show large fluctuations in employment because they need greater or fewer employees at certain times of the year. Ski resorts, for instance, hire far more employees in the winter months to accommodate the snow skiing season and schools have large changes at the beginning and the ending of the school year. By seasonally adjusting employment, statisticians attempt to remove the predictable seasonal patterns in order to isolate the underlying month-to-month economic changes in the employment and unemployment series. The adjustment consists of either raising or lowering the actual estimate reported by a certain volume or percentage, which represent the expected seasonal increases or decreases that had historically occurred.
Typically, the monthly employment and unemployment numbers reported in the news are seasonally adjusted data. Seasonally adjusted data are useful when comparing different months of data, whereas not seasonally adjusted data should only be compared to the same month in prior years. Annual average estimates are calculated from the not seasonally adjusted data series.
How does CES data compare to CWIA’s other primary source of jobs data, the Quarterly Census of Employment and Wages (QCEW)?
The CES and Quarterly Census of Employment and Wages (QCEW) programs are related but do not report the exact same information at the same frequency. The QCEW program publishes a quarterly count of employment and wages covering 98 percent of U.S. jobs, available at the county, Metropolitan Statistical Area (MSA), State, and National levels by industry. The CES program surveys about 143,000 businesses and government agencies, representing approximately 588,000 worksites, in order to provide detailed industry data on employment, hours, and earnings of workers on nonfarm payrolls on a monthly basis.
Unemployment Insurance (UI) tax reports, submitted by nearly all businesses in the U.S., are used as both the input data for QCEW data and as the majority of the sample frame for the CES survey and cover almost all private industries and government agencies. CES employment figures are benchmarked each year in large part using data from the QCEW program because both programs use the pay period including the 12th of the month as the reference period for employment.
QCEW quarterly wages include total compensation paid during the calendar quarter to all workers; CES hours and earnings data are reported for all employees and for production or nonsupervisory employees in private industry who received pay (whether they worked or not) during any part of the pay period that includes the 12th day of the month. CES earnings do not include irregular bonuses or retroactive pay.
CES data are published 3 weeks after the week that includes the 12th of the month, typically the first Friday of the following month. QCEW data are published much later, approximately 6 months after the end of the reference period.
How does CES employment data compare to labor force employment collected by the Current Population Survey (CPS)?
The CES program is a monthly survey of business establishments (or jobs). CES produces estimates on the number of employees on nonfarm payrolls. The Current Population Survey (CPS) is a monthly survey of households (or people). The household survey produces estimates about the labor force, including the number of people who are employed (or unemployed).
The household survey administered by the CPS program and establishment survey administered by the CES program both produce sample-based estimates of employment and both have strengths and limitations. The establishment survey employment series has a smaller margin of error on the measurement of month-to-month change than the household survey because of its much larger sample size. An over-the-month employment change of about 100,000 is statistically significant in the establishment survey, while the threshold for a statistically significant change in the household survey is about 400,000. However, the household survey has a more expansive scope than the establishment survey because it includes self-employed workers whose businesses are unincorporated, unpaid family workers, agricultural workers, and private household workers, who are excluded by the establishment survey. The household survey also provides estimates of employment for demographic groups.
How are CES estimates categorized?
CES estimates are categorized by ownership and industry. Respondents are assigned an ownership code — private or public with public ownership further divided into Federal, State, or local. Respondents are then assigned a North American Industry Classification System (NAICS) code. NAICS codes group establishments into industries based on the activity in which they are primarily engaged.
Why doesn’t CES collect agricultural employment?
CES draws its sample and sets its benchmark employment level from the business establishment list maintained by the Quarterly Census of Employment and Wages (QCEW) program. This universe for business establishments is based on Unemployment Insurance (UI) administrative records, so workers who are not covered by UI will not be captured. In Agriculture there are numerous exemptions to requirements for UI coverage, making the sample frame for Agriculture insufficient for calculating statistically sound estimates. In addition, a substantial number of Agricultural enterprises are self-proprietorships, which are out of scope for the CES survey.
Historically, the U.S. Department of Agriculture’s Census of Agriculture has been the primary survey used to measure farm labor. The Census of Agriculture is available at http://www.agcensus.usda.gov/index.php