The NAICS was created to replace the U.S. Standard Industrial Classification (SIC) system to modernize it, so that it would be able to relate to the constantly changing economy. The new system also allows for better comparability between all North American countries, which is important because of the increased trade between NAFTA countries. To ensure that the NAICS will be able to keep pace with changing economic conditions it will be reviewed every five years.
Investment dictionary. Academic. 2012.