Answered By: Rich Gause Last Updated: Dec 12, 2014 Views: 4342
Economic Census: Concentration Ratios (1992+) "classify industries by the percent of output accounted for by the largest 4, 8, 20 and 50 companies."
The Herfindahl-Hirschman Index (HHI) is calculated for the 50 largest companies (manufacturing industries only).
More information is available on the Concentration Ratios page of the Business & Economics -- Government Resources guide.
[LibChat Widget goes here.]