Sectoring schemes provide a means of classifying and aggregating Industry and Commodity data. Each database source can have its own unique format or scheme for presenting Industry data (e.g. IMPLAN scheme or the REA scheme). An Industrial classification scheme allows categorization according to the type of products or services produced by the Industry or Industries.

Employment and Value Added data used in IMPLAN originates from surveys of Industry establishments. This establishment may be a small business with a single location, or it may be a branch location of a large firm. Each establishment in the defined region is counted separately on the covered (social security or unemployment) employment rolls. When the establishment submits a report or responds to a census or a survey, its data are collected and assigned an establishment code depending on the primary product produced by that establishment.

The Industry classification scheme used for all federal government industry based data sets is the 6-digit North American Industrial Classification Scheme (NAICS), as described in the most current NAICS manual, published by the Office of Management and Budget.

This scheme was adopted in 1997 and replaced the previously used Standard Industrial Classification (SIC) codes. Unlike the SIC, NAICS was developed jointly by the United States, Mexico, and Canada to allow for comparability between all North American Industrial data.

The current NAICS scheme is 2017. NAICS reports five levels of Industry detail, ranging from the 2-digit detail (the most aggregate) to the 6-digit (the most detailed). To learn more about the history of NAICS click here. Certain IMPLAN Sectors - including the construction Sectors (50-62), Sector 449 - Owner-occupied dwellings, Sector 525 - Private households, and Sectors 526-546, do not follow a normal NAICS pattern. Read more information about these Specialty Sectors. Read more for additional information on the IMPLAN Sectoring scheme and for a listing of the current 546 scheme.



A major data source used to derive IMPLAN databases is the Bureau of Economic Analysis' Regional Economic Accounts (REA - formerly known as REIS). At the state level, REA reports in 3-digit NAICS detail for employment and income. At the county level, income is reported at 3-digit NAICS but employment is provided at the 2-digit NAICS detail.


Data from the Bureau of Labor Statistics (BLS) is used for deflators and some output estimates. The BLS uses a different sectoring scheme, again based on the NAICS code system.


IMPLAN's current 546-sector scheme is based on the Bureau of Economic Analysis' latest Benchmark Input-Output Study. Since every five years the BEA updates their input-output accounts, it means that on those years, IMPLAN data sets also undergo important updates as well. In late 2018, the BEA released its 2012 industry statistics and benchmark make-use tables (also known as I-O tables) which include methodological improvements to more accurately reflect the ever-changing national economy. For more information, visit BEA Benchmark & The New 546 Sectoring Scheme.

IMPLAN Database years Number of IMPLAN Sectors BEA Benchmarks
1996-2000 528 1987 and 1992
2001-2004, 2006 509 1997
2007-2012 440 2002
2013-2017 536 2007 with parts of 1997 and 2002
2018+ 546 2012


Prior to NAICS, this was the most common scheme as described in the 1987 Standard Industrial Classification Manual. This scheme had four levels of detail ranging from 1-digit detail as the most aggregate to 4-digit as the most detailed. IMPLAN datasets prior to 2001 are SIC-based.



BEA Benchmark & The New 546 Sectoring Scheme

U.S. 546 Industries, Conversions, & Bridges


Written August 30, 2023