{
 "page": "https://prediction-market-use-cases.vercel.app/kalshi/category/transportation/",
 "source": "Becker Kalshi dataset (github.com/Jon-Becker/prediction-market-analysis); categories from Kalshi public API GET /trade-api/v2/series fetched 2026-10-17",
 "snapshot": "2026-10-17",
 "units": {
  "contracts": "sum of markets.volume (contracts, not dollars)"
 },
 "data": {
  "markets": 1574,
  "events": 472,
  "nseries": 23,
  "vol": 2535440,
  "zero": 475,
  "settled": 1573,
  "yes": 760,
  "no": 813,
  "first": "2021-07-13",
  "last": "2025-08-08",
  "by_year": [
   {
    "year": 2021,
    "markets": 149,
    "contracts": 756172,
    "never_traded": 1,
    "settled": 149,
    "yes": 65
   },
   {
    "year": 2022,
    "markets": 552,
    "contracts": 645986,
    "never_traded": 170,
    "settled": 552,
    "yes": 137
   },
   {
    "year": 2023,
    "markets": 277,
    "contracts": 204954,
    "never_traded": 120,
    "settled": 277,
    "yes": 197
   },
   {
    "year": 2024,
    "markets": 585,
    "contracts": 783976,
    "never_traded": 184,
    "settled": 585,
    "yes": 355
   },
   {
    "year": 2025,
    "markets": 11,
    "contracts": 144352,
    "never_traded": 0,
    "settled": 10,
    "yes": 6
   }
  ],
  "top_series": [
   {
    "series": "TSAW",
    "title": "TSA check-ins this week",
    "markets": 945,
    "contracts": 1352108,
    "never_traded": 305
   },
   {
    "series": "MTA",
    "title": "NYC subway riders",
    "markets": 45,
    "contracts": 218513,
    "never_traded": 0
   },
   {
    "series": "TSA",
    "title": "TSA daily check-ins",
    "markets": 81,
    "contracts": 218432,
    "never_traded": 1
   },
   {
    "series": "KXTSAMAX",
    "title": "TSA min/max",
    "markets": 1,
    "contracts": 153787,
    "never_traded": 0
   },
   {
    "series": "KXREALID",
    "title": "TSA real ID",
    "markets": 1,
    "contracts": 117223,
    "never_traded": 0
   },
   {
    "series": "FLIGHTJFK",
    "title": "JFK International Airport total flight delays and cancellations",
    "markets": 142,
    "contracts": 98216,
    "never_traded": 32
   },
   {
    "series": "FLIGHTORD",
    "title": "O'Hare International Airport total delays and cancellations",
    "markets": 142,
    "contracts": 85821,
    "never_traded": 44
   },
   {
    "series": "BOEINGCEOCHANGE",
    "title": "New Boeing CEO",
    "markets": 1,
    "contracts": 76291,
    "never_traded": 0
   },
   {
    "series": "PORTLA",
    "title": "Ships anchored in LA",
    "markets": 11,
    "contracts": 56770,
    "never_traded": 0
   },
   {
    "series": "FLIGHTLAX",
    "title": "Los Angeles International Airport total delays and cancellations",
    "markets": 138,
    "contracts": 41467,
    "never_traded": 70
   }
  ]
 }
}