{"license":"https://creativecommons.org/licenses/by/4.0/","dataset":"industry-history","count":4,"years":[2017,2022],"metric":"hhi","sources":[{"id":"census-ecnsize-concentration-2017","title":"2017 Economic Census Concentration of Largest Firms","publisher":"U.S. Census Bureau","citationAuthor":"U.S. Census Bureau","citationAuthorType":"organization","citationYear":2020,"url":"https://www2.census.gov/programs-surveys/economic-census/data/2017/sector00/EC1700SIZECONCEN.zip","description":"Economy-wide national firm concentration statistics by 2017 NAICS industry including revenue-based HHI and largest-firm concentration ratios.","sourceType":"public_dataset","accessDate":"2026-07-18","citationText":"U.S. Census Bureau, 2017 Economic Census, EC1700SIZECONCEN: Selected Sectors - Concentration of Largest Firms for the United States, released November 2020.","licenseNote":"Public federal government dataset","archivedUrl":null,"profileHref":"/sources/census-ecnsize-concentration-2017"},{"id":"census-ecnsize-concentration-2022","title":"2022 Economic Census Concentration of Largest Firms","publisher":"U.S. Census Bureau","citationAuthor":"U.S. Census Bureau","citationAuthorType":"organization","citationYear":2025,"url":"https://www2.census.gov/programs-surveys/economic-census/data/2022/sector00/EC2200SIZECONCEN.zip","description":"Economy-wide national firm concentration statistics by 2022 NAICS industry including revenue-based HHI and largest-firm concentration ratios.","sourceType":"public_dataset","accessDate":"2026-07-17","citationText":"U.S. Census Bureau, 2022 Economic Census, EC2200SIZECONCEN: Selected Sectors - Concentration of Largest Firms for the United States, released April 2025.","licenseNote":"Public federal government dataset","archivedUrl":null,"profileHref":"/sources/census-ecnsize-concentration-2022"}],"guardrail":"Five-year deltas are published only for rows whose NAICS code and industry label are identical in the 2017 and 2022 Census tables. This strict match is a conservative screening rule, not an official NAICS concordance or evidence of causation. Revenue changes are nominal and are not adjusted for inflation.","compositionGuardrail":null,"compositionSummary":null,"hhiDistributionGuardrail":"The benchmark contains strict six-digit NAICS matches with HHI published in both 2017 and 2022. Revenue and employment views hold each row's 2022 scale fixed, so band-share changes isolate HHI-band migration within this published pair universe. These distributions are not whole-economy concentration indexes, legal antitrust markets, liability findings, or causal estimates.","hhiDistributionSummary":{"benchmarkCount":789,"pairedCount":543,"coveragePercent":68.8,"medianHhi2017":265.5,"medianHhi2022":271.3,"medianHhiChange":3.6,"upwardBandCount":35,"downwardBandCount":27,"sameBandCount":481,"bands":[{"id":"under-500","label":"0-499","count2017":383,"count2022":383,"share2017Pct":70.534,"share2022Pct":70.534,"sharePointChange":0},{"id":"500-999","label":"500-999","count2017":106,"count2022":100,"share2017Pct":19.521,"share2022Pct":18.416,"sharePointChange":-1.105},{"id":"1000-1499","label":"1,000-1,499","count2017":37,"count2022":41,"share2017Pct":6.814,"share2022Pct":7.551,"sharePointChange":0.737},{"id":"1500-2499","label":"1,500-2,499","count2017":13,"count2022":14,"share2017Pct":2.394,"share2022Pct":2.578,"sharePointChange":0.184},{"id":"2500-plus","label":"2,500+","count2017":4,"count2022":5,"share2017Pct":0.737,"share2022Pct":0.921,"sharePointChange":0.184}]},"summary":{"currentCount":1866,"historicalCount":1935,"matchedCodeCount":1680,"strictMatchCount":1640,"classificationChangedCount":40,"new2022Count":186,"historicalOnlyCount":255,"currentDetailedCount":899,"historicalDetailedCount":943,"strictDetailedCount":789,"benchmarkCount":789,"pairedCount":543,"unavailableCount":246,"increasedCount":306,"decreasedCount":237,"unchangedCount":0,"medianChange":3.6},"filters":{"naics":null,"naicsMatched":null,"codes":["313220","213113","332117","213115"],"codesMatched":true,"matchedCodes":["313220","213113","332117","213115"],"unmatchedCodes":[],"branch":null,"branchMatched":null,"query":null,"level":6,"levelMatched":true,"sector":null,"sectorMatched":null,"metric":"hhi","metricMatched":true,"status":"strict_match","statusMatched":true,"availability":"all","availabilityMatched":true,"direction":"all","directionMatched":true,"hhiFromBand":null,"hhiFromBandMatched":true,"hhiToBand":null,"hhiToBandMatched":true,"sort":"change","sortMatched":true,"order":"desc","orderMatched":true},"rows":[{"naicsCode":"213113","industryLevel":6,"sectorCode":"21","sectorName":"Mining, quarrying, and oil and gas extraction","industryName2022":"Support activities for coal mining","industryName2017":"Support activities for coal mining","comparisonStatus":"strict_match","fromYear":2017,"toYear":2022,"metric":"hhi","fromValue":306,"toValue":395.3,"absoluteChange":89.3,"percentChange":29.2,"direction":"increased","hhi2017":306,"hhi2022":395.3,"hhiChange":89.3,"hhiBand2017":"under-500","hhiBand2022":"under-500","hhiBandMovement":"same","cr4Pct2017":26.2,"cr4Pct2022":31.3,"cr4PointChange":5.1,"cr8Pct2017":40,"cr8Pct2022":46.1,"cr8PointChange":6.1,"revenueThousands2017":1067765,"revenueThousands2022":889272,"nominalRevenueChangeThousands":-178493,"employees2017":3865,"employees2022":3020,"employeeChange":-845,"firms2017":186,"firms2022":118,"firmChange":-68,"sourceId2017":"census-ecnsize-concentration-2017","sourceId2022":"census-ecnsize-concentration-2022","profileHref":"/industries/213113"},{"naicsCode":"313220","industryLevel":6,"sectorCode":"31","sectorName":"Manufacturing","industryName2022":"Narrow fabric mills and schiffli machine embroidery","industryName2017":"Narrow fabric mills and schiffli machine embroidery","comparisonStatus":"strict_match","fromYear":2017,"toYear":2022,"metric":"hhi","fromValue":485.9,"toValue":385.1,"absoluteChange":-100.8,"percentChange":-20.7,"direction":"decreased","hhi2017":485.9,"hhi2022":385.1,"hhiChange":-100.8,"hhiBand2017":"under-500","hhiBand2022":"under-500","hhiBandMovement":"same","cr4Pct2017":34.6,"cr4Pct2022":30.8,"cr4PointChange":-3.8,"cr8Pct2017":50.2,"cr8Pct2022":46.1,"cr8PointChange":-4.1,"revenueThousands2017":877455,"revenueThousands2022":983686,"nominalRevenueChangeThousands":106231,"employees2017":5255,"employees2022":5224,"employeeChange":-31,"firms2017":169,"firms2022":154,"firmChange":-15,"sourceId2017":"census-ecnsize-concentration-2017","sourceId2022":"census-ecnsize-concentration-2022","profileHref":"/industries/313220"},{"naicsCode":"332117","industryLevel":6,"sectorCode":"31","sectorName":"Manufacturing","industryName2022":"Powder metallurgy part manufacturing","industryName2017":"Powder metallurgy part manufacturing","comparisonStatus":"strict_match","fromYear":2017,"toYear":2022,"metric":"hhi","fromValue":531.3,"toValue":387.3,"absoluteChange":-144,"percentChange":-27.1,"direction":"decreased","hhi2017":531.3,"hhi2022":387.3,"hhiChange":-144,"hhiBand2017":"500-999","hhiBand2022":"under-500","hhiBandMovement":"lower","cr4Pct2017":41,"cr4Pct2022":31.6,"cr4PointChange":-9.4,"cr8Pct2017":53.7,"cr8Pct2022":46,"cr8PointChange":-7.7,"revenueThousands2017":2328404,"revenueThousands2022":2209252,"nominalRevenueChangeThousands":-119152,"employees2017":9543,"employees2022":9411,"employeeChange":-132,"firms2017":115,"firms2022":119,"firmChange":4,"sourceId2017":"census-ecnsize-concentration-2017","sourceId2022":"census-ecnsize-concentration-2022","profileHref":"/industries/332117"},{"naicsCode":"213115","industryLevel":6,"sectorCode":"21","sectorName":"Mining, quarrying, and oil and gas extraction","industryName2022":"Support activities for nonmetallic minerals (except fuels) mining","industryName2017":"Support activities for nonmetallic minerals (except fuels) mining","comparisonStatus":"strict_match","fromYear":2017,"toYear":2022,"metric":"hhi","fromValue":728.2,"toValue":295,"absoluteChange":-433.2,"percentChange":-59.5,"direction":"decreased","hhi2017":728.2,"hhi2022":295,"hhiChange":-433.2,"hhiBand2017":"500-999","hhiBand2022":"under-500","hhiBandMovement":"lower","cr4Pct2017":45.5,"cr4Pct2022":28.1,"cr4PointChange":-17.4,"cr8Pct2017":52.7,"cr8Pct2022":40.9,"cr8PointChange":-11.8,"revenueThousands2017":796907,"revenueThousands2022":1088569,"nominalRevenueChangeThousands":291662,"employees2017":2854,"employees2022":4097,"employeeChange":1243,"firms2017":194,"firms2022":193,"firmChange":-1,"sourceId2017":"census-ecnsize-concentration-2017","sourceId2022":"census-ecnsize-concentration-2022","profileHref":"/industries/213115"}]}