Change in Industry Classification Systems

The year 2000 data was the last from the Quarterly Census of Employment and Wages (ES-202) program using the 1987 Standard Industrial Classification (SIC) system. With the release of data for 2001, the program switched to the 2002 version of the North American Industry Classification System (NAICS) as the basis for the assignment and tabulation of economic data by industry. NAICS is the product of a cooperative effort on the part of the statistical agencies of the United States, Canada, and Mexico. Due to differences in NAICS and SIC structures, data for 2001 is not comparable to the SIC-based data for earlier years.

NAICS uses a production-oriented approach to categorize economic units. Units with similar production processes are classified in the same industry. NAICS focuses on how products and services are created, as opposed to the SIC focus on what is produced. This approach yields significantly different industry groupings than those produced by the SIC approach.

Data users will be able to work with new NAICS industrial groupings that better reflect the workings of the U.S. economy. For example, a new industry sector called Information brings together units that turn information into a commodity with units that distribute the commodity and units that provide information services. Information's major components are publishing, broadcasting, telecommunications, information services, and data processing. Under the SIC system, these units were spread across the manufacturing, communications, business services, and amusement services groups. Another new sector of interest is Professional, Scientific, and Technical Services. This sector is comprised of establishments engaged in activities where human capital is the major input.

Users interested in more information about NAICS can access the BLS web page at or the Bureau of the Census web page at  The NAICS 2002 manual is available from the National Technical Information Service.


Last Modified Date: February 26, 2003