Data infrastructure / open access
Public data catalog
Download the records behind the research, including market shares, concentration measures, official events, and source references. Coverage and missing values are documented for each dataset.
Source records move through market definitions, concentration calculations, confidence labels, and public data endpoints — 45 source records, 12 market profiles, 235808 record rows plus a 1 row summary endpoint across 62 API endpoints.
Record rows
235,808
Sources
45
Endpoints
62
Aug 15, 2026
Latest source review
62
Dataset families
4
Source types
Market-definition atlas
What market is this metric measuring?
Inspect each product boundary, geography, denominator, proxy choice, and permitted comparison use before treating concentration values as economic evidence.
Selected definition contract
U.S. domestic airline passengers
Product boundary
Domestic scheduled airline passenger traffic
Geographic boundary
United States domestic itineraries
Measurement basis
Carrier share of domestic scheduled passengers
Denominator
Passengers reported in the BTS domestic market-share table for the 12 months ending February 2026
Included
Named carriers and the published aggregate Other category
Excluded
Individual carriers inside Other are not separately identified
Method and limitations
Use sourced carrier passenger shares for top-firm and CR4 screens; withhold HHI while Other remains aggregated.
The aggregate Other row prevents a complete firm-level distribution and therefore prevents a publishable HHI.
Boundary source
TranStats airline domestic market share March 2025-February 2026
Bureau of Transportation Statistics · accessed 2026-05-16
Open data needs public interpretation.
The API is a starting point, not a legal conclusion. Pair downloads with methodology notes, source records, and the data-gaps report when citing market concentration.