Bureau of Labor Statistics > Current Employment Statistics > Methods > Industry Classification Overview

Caution

The classification system conversion information on this page details a prior conversion. More information about NAICS, previous versions of NAICS, and the current classification system can be obtained at www.bls.gov/ces/naics/home.htm.

Notice of Conversion to the North American Industry Classification System 2002 and Other Series Changes in June 2003

With the release of May 2003 data on June 6, 2003, the Current Employment Statistics (CES) National Nonfarm Payroll series underwent a number of changes. The basis for industry classification changed from the Standard Industrial Classification System (SIC) 1987 to the North American Industry Classification System (NAICS) 2002. For more information about NAICS in the CES program, see www.bls.gov/ces/naics/home.htm. In addition, the sample redesign was completed for the remaining private sector industries, the CES series incorporated concurrent seasonal adjustment, and the Federal government series were revised slightly in scope and definition.

Conversion to NAICS 2002
- Distribution of Employment from SIC Division to NAICS Supersector
- Ratios of Employment from SIC to NAICS and from NAICS to SIC
Completion of the CES Sample Redesign
Concurrent Seasonal Adjustment
Changes to Federal Government Series

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Conversion to NAICS 2002

NAICS has replaced the SIC system. The CES survey first published National data on a NAICS 2002 basis with the release of May 2003 data on June 6, 2003. SIC-based data is no longer produced or published; it is still available but is not updated past April 2003. Most historical all employee (AE) series were reconstructed back to 1990 as part of the NAICS reconstruction. Other data types have varying start years. Most production and nonsupervisory employees, hours, and earnings series start in either 2001 or 2003, and AE hours and earnings series begin in 2006. Other series that were highly interchangeable with an SIC series have history going farther back in time. The NAICS-based reconstruction effort covered all CES published datatypes. For a complete list of series published by CES as well as start years for AE series, visit www.bls.gov/web/empsit/cesseriespub.htm. For further information about the conversion from SIC to NAICS, see the June 2006 article "Recent Changes in the National Current Employment Statistics Survey" (PDF) by BLS Economist Teresa Morisi.

Distribution of Employment from Standard Industry Classification System Divisions to North American Industry Classification System Supersectors

For the private sector, the following table shows the distribution of Current Employment Statistics (CES) employment between Standard Industry Classification System (SIC) divisions and North American Industry Classification System (NAICS) supersectors. For example, for the supersector Mining and logging⁽¹⁾, 87.3 percent of employment comes from the Mining division and 12.7 percent from the Manufacturing division. The table was prepared using first quarter 2001 data from the Quarterly Census of Employment and Wages Program and can be used to evaluate time series breaks in the CES data series.

Distribution of Employment from SIC Divisions to NAICS Supersectors (in thousands)
NAICS Supersectors		SIC Divisions
NAICS Supersectors		Mining	Construction	Manufacturing	Transportation and public utilities	Wholesale trade	Retail trade	Finance, insurance, and real estate	Services
Mining and logging⁽¹⁾	Level	516	⁽²⁾	75	⁽²⁾	⁽²⁾	⁽²⁾	⁽²⁾	⁽²⁾
Mining and logging⁽¹⁾	Percent	87.3	⁽³⁾	12.7	⁽³⁾	⁽³⁾	⁽³⁾	⁽³⁾	⁽³⁾
Construction	Level	17	6,289	⁽²⁾	⁽²⁾	⁽²⁾	⁽²⁾	86	79
Construction	Percent	.3	97.2	⁽³⁾	⁽³⁾	⁽³⁾	⁽³⁾	1.3	1.2
Manufacturing	Level	⁽²⁾	⁽²⁾	16,503	⁽²⁾	31	148	⁽²⁾	129
Manufacturing	Percent	⁽³⁾	⁽³⁾	98.2	⁽³⁾	.2	.9	⁽³⁾	.8
Trade, transportation, and utilities	Level	⁽²⁾	1	71	4,360	6,593	14,381	⁽²⁾	125
Trade, transportation, and utilities	Percent	⁽³⁾	⁽³⁾	.3	17.1	25.8	56.3	⁽³⁾	.5
Information	Level	⁽²⁾	⁽²⁾	752	1,670	⁽²⁾	1	9	1,263
Information	Percent	⁽³⁾	⁽³⁾	20.3	45.2	⁽³⁾	⁽³⁾	.2	34.2
Financial activities	Level	⁽²⁾	⁽²⁾	⁽²⁾	38	⁽²⁾	25	6,882	671
Financial activities	Percent	⁽³⁾	⁽³⁾	⁽³⁾	.5	⁽³⁾	.3	90.4	8.8
Professional and business services	Level	16	66	613	658	156	374	432	14,173
Professional and business services	Percent	.1	.4	3.7	4.0	.9	2.3	2.6	86.0
Education and health services	Level	⁽²⁾	⁽²⁾	4	101	⁽²⁾	⁽²⁾	⁽²⁾	14,602
Education and health services	Percent	⁽³⁾	⁽³⁾	⁽³⁾	.7	⁽³⁾	⁽³⁾	⁽³⁾	99.3
Leisure and hospitality	Level	⁽²⁾	⁽²⁾	⁽²⁾	24	⁽²⁾	8,147	8	3,402
Leisure and hospitality	Percent	⁽³⁾	⁽³⁾	⁽³⁾	.2	⁽³⁾	70.3	.1	29.4
Other services	Level	⁽²⁾	⁽²⁾	13	5	⁽²⁾	6	103	3,614
Other services	Percent	⁽³⁾	⁽³⁾	.3	.1	⁽³⁾	.2	2.8	96.5

⁽¹⁾ Previously titled Natural resources and mining.
⁽²⁾ Less than 1,000.
⁽³⁾ Less than 0.05 percent.

Ratios of Employment from SIC to NAICS and from NAICS to SIC

The following tables show ratios of employment from 2-,3-, and 4-digit SIC series to NAICS, and from NAICS to 2-, 3-, and 4-digit SIC series for the private sector. The tables were prepared using first quarter 2001 data from the Quarterly Census of Employment and Wages program and can be used to evaluate time series breaks and correspondence between SIC and NAICS in the CES series. Ratios may not add up to 100 percent for an SIC or NAICS series because ratios less than 1 percent were excluded, and not all NAICS industries will be published under CES — part of an SIC series may go to an unpublished NAICS industry or a combined NAICS series.

Completion of the CES Sample Redesign

On June 6, 2003, CES completed phasing in the sample redesign. The redesign converted the CES survey from a quota-based sample to a probability-based sample. The final stage of sample redesign phase-in resulted in level shifts for average weekly hours, average hourly earnings, production worker, and women worker series. New levels for these series were computed from NAICS/probability sample-based averages. For further information, read the section titled "Completion of probability sample redesign" in the June 2006 article "Recent Changes in the National Current Employment Statistics Survey" (PDF) by BLS Economist Teresa Morisi.

Concurrent Seasonal Adjustment

Beginning in June 2003, the CES program converted from its current practice of updating seasonal factors twice a year to updating them every month. Concurrent seasonal adjustment is technically superior to semiannual updates because it uses all available monthly estimates, including those for the current month, thereby eliminating the need to project the seasonal factors. With the introduction of concurrent seasonal adjustment, BLS no longer publishes seasonal factors for CES National estimates. For more information, please read the following paper on concurrent seasonal adjustment. (HTML)

Changes to Federal Government Series

The CES series for Federal government employment was revised slightly in scope and definition due to a change in source data and estimation methods. The previous National series was an end-of-month federal employee count produced by the Office of Personnel Management that excluded some workers, mostly employees who work in Department of Defense-owned establishments such as military base commissaries. Beginning in June 2003, the CES National series includes these workers. Also, Federal government employment is now estimated from a sample of federal establishments, is benchmarked annually to counts from unemployment insurance tax records, and reflects employee counts as of the pay period including the 12th of the month, consistent with other CES industry series. The historical time series for Federal government employment was revised to reflect these changes.

Last Modified Date: January 24, 2022