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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 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