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North American Industry Classification System

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History of NAICS - Early Development Documents

Issue Papers Relating to Industry Classification


ECPC Concept Reports

  • ECPC Report 1, "Economic Concepts in SIC Industries" [PDF, 47MB]
  • ECPC Report 2, "The Heterogeneity Index: A Quantitative Tool to Support Industrial Classifications" [PDF, 15MB]


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Source: U.S. Census Bureau | North American Industry Classification System (NAICS) | (888) 756-2427 naics@census.gov | Last Revised: November 05, 2014