{"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":["488119","339112","332321","334513"],"codesMatched":true,"matchedCodes":["488119","339112","332321","334513"],"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":"332321","industryLevel":6,"sectorCode":"31","sectorName":"Manufacturing","industryName2022":"Metal window and door manufacturing","industryName2017":"Metal window and door manufacturing","comparisonStatus":"strict_match","fromYear":2017,"toYear":2022,"metric":"hhi","fromValue":184,"toValue":225.5,"absoluteChange":41.5,"percentChange":22.6,"direction":"increased","hhi2017":184,"hhi2022":225.5,"hhiChange":41.5,"hhiBand2017":"under-500","hhiBand2022":"under-500","hhiBandMovement":"same","cr4Pct2017":20.4,"cr4Pct2022":24.8,"cr4PointChange":4.4,"cr8Pct2017":32.3,"cr8Pct2022":35.1,"cr8PointChange":2.8,"revenueThousands2017":12528628,"revenueThousands2022":19486133,"nominalRevenueChangeThousands":6957505,"employees2017":51197,"employees2022":58572,"employeeChange":7375,"firms2017":894,"firms2022":876,"firmChange":-18,"sourceId2017":"census-ecnsize-concentration-2017","sourceId2022":"census-ecnsize-concentration-2022","profileHref":"/industries/332321"},{"naicsCode":"488119","industryLevel":6,"sectorCode":"48","sectorName":"Transportation and warehousing","industryName2022":"Other airport operations","industryName2017":"Other airport operations","comparisonStatus":"strict_match","fromYear":2017,"toYear":2022,"metric":"hhi","fromValue":302.4,"toValue":247.1,"absoluteChange":-55.3,"percentChange":-18.3,"direction":"decreased","hhi2017":302.4,"hhi2022":247.1,"hhiChange":-55.3,"hhiBand2017":"under-500","hhiBand2022":"under-500","hhiBandMovement":"same","cr4Pct2017":29.4,"cr4Pct2022":26,"cr4PointChange":-3.4,"cr8Pct2017":43,"cr8Pct2022":36.4,"cr8PointChange":-6.6,"revenueThousands2017":8724615,"revenueThousands2022":14260232,"nominalRevenueChangeThousands":5535617,"employees2017":116181,"employees2022":108109,"employeeChange":-8072,"firms2017":1116,"firms2022":1071,"firmChange":-45,"sourceId2017":"census-ecnsize-concentration-2017","sourceId2022":"census-ecnsize-concentration-2022","profileHref":"/industries/488119"},{"naicsCode":"339112","industryLevel":6,"sectorCode":"31","sectorName":"Manufacturing","industryName2022":"Surgical and medical instrument manufacturing","industryName2017":"Surgical and medical instrument manufacturing","comparisonStatus":"strict_match","fromYear":2017,"toYear":2022,"metric":"hhi","fromValue":332.1,"toValue":271.3,"absoluteChange":-60.8,"percentChange":-18.3,"direction":"decreased","hhi2017":332.1,"hhi2022":271.3,"hhiChange":-60.8,"hhiBand2017":"under-500","hhiBand2022":"under-500","hhiBandMovement":"same","cr4Pct2017":29.9,"cr4Pct2022":26.3,"cr4PointChange":-3.6,"cr8Pct2017":42.4,"cr8Pct2022":35.9,"cr8PointChange":-6.5,"revenueThousands2017":39680612,"revenueThousands2022":40260371,"nominalRevenueChangeThousands":579759,"employees2017":111429,"employees2022":121079,"employeeChange":9650,"firms2017":1064,"firms2022":1033,"firmChange":-31,"sourceId2017":"census-ecnsize-concentration-2017","sourceId2022":"census-ecnsize-concentration-2022","profileHref":"/industries/339112"},{"naicsCode":"334513","industryLevel":6,"sectorCode":"31","sectorName":"Manufacturing","industryName2022":"Instruments and related products manufacturing for measuring, displaying, and controlling industrial process variables","industryName2017":"Instruments and related products manufacturing for measuring, displaying, and controlling industrial process variables","comparisonStatus":"strict_match","fromYear":2017,"toYear":2022,"metric":"hhi","fromValue":null,"toValue":297.1,"absoluteChange":null,"percentChange":null,"direction":"unavailable","hhi2017":null,"hhi2022":297.1,"hhiChange":null,"hhiBand2017":null,"hhiBand2022":"under-500","hhiBandMovement":null,"cr4Pct2017":32.3,"cr4Pct2022":27.9,"cr4PointChange":-4.4,"cr8Pct2017":42.4,"cr8Pct2022":36.5,"cr8PointChange":-5.9,"revenueThousands2017":10470261,"revenueThousands2022":14234763,"nominalRevenueChangeThousands":3764502,"employees2017":32626,"employees2022":41518,"employeeChange":8892,"firms2017":745,"firms2022":841,"firmChange":96,"sourceId2017":"census-ecnsize-concentration-2017","sourceId2022":"census-ecnsize-concentration-2022","profileHref":"/industries/334513"}]}