Terms like "sector" and "industry" are often used interchangeably. For precision, this chapter uses the terms in the same manner as the North American Industry Classification System (NAICS). In NAICS, sectors contain subsectors, subsectors contain industry groups, and industry groups contain industries, as shown in the following example:

Sector : Transportation and warehousing (NAICS 48-49)

Subsector : Truck transportation (NAICS 484)

Industry group : General freight trucking (NAICS 4841)

Industry : General freight trucking, long-distance (NAICS 48412)

Industry detail : General freight trucking, long-distance, less than truckload (NAICS 484122)

SOURCE : Bureau of Transportation Statistics, 2016