{
 "page": "https://prediction-market-use-cases.vercel.app/kalshi/category/world/",
 "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": 368,
  "events": 161,
  "nseries": 85,
  "vol": 4903096,
  "zero": 45,
  "settled": 325,
  "yes": 101,
  "no": 224,
  "first": "2021-07-03",
  "last": "2025-11-09",
  "by_year": [
   {
    "year": 2021,
    "markets": 95,
    "contracts": 1430463,
    "never_traded": 2,
    "settled": 95,
    "yes": 34
   },
   {
    "year": 2022,
    "markets": 19,
    "contracts": 144580,
    "never_traded": 0,
    "settled": 19,
    "yes": 6
   },
   {
    "year": 2023,
    "markets": 12,
    "contracts": 156275,
    "never_traded": 1,
    "settled": 12,
    "yes": 7
   },
   {
    "year": 2024,
    "markets": 10,
    "contracts": 570024,
    "never_traded": 0,
    "settled": 6,
    "yes": 1
   },
   {
    "year": 2025,
    "markets": 232,
    "contracts": 2601754,
    "never_traded": 42,
    "settled": 193,
    "yes": 53
   }
  ],
  "top_series": [
   {
    "series": "KXRAINNOSB",
    "title": "Super Bowl Sunday rain",
    "markets": 1,
    "contracts": 857668,
    "never_traded": 0
   },
   {
    "series": "RECSS",
    "title": "Quarter of negative GDP growth by 2022 Q2",
    "markets": 1,
    "contracts": 597086,
    "never_traded": 0
   },
   {
    "series": "KXFERTILITYSK",
    "title": "Fertility in South Korea",
    "markets": 1,
    "contracts": 348834,
    "never_traded": 0
   },
   {
    "series": "RAINNY",
    "title": "NYC rain",
    "markets": 31,
    "contracts": 310582,
    "never_traded": 0
   },
   {
    "series": "KXNEWPOPEDATE",
    "title": "New Pope date",
    "markets": 5,
    "contracts": 215574,
    "never_traded": 0
   },
   {
    "series": "KXNEWPOPEROUNDS",
    "title": "New pope rounds of voting",
    "markets": 8,
    "contracts": 178431,
    "never_traded": 0
   },
   {
    "series": "KXNYCBOROUGHWINMAN",
    "title": "Winner of Borough",
    "markets": 2,
    "contracts": 171026,
    "never_traded": 0
   },
   {
    "series": "KXFOOTBALL1001",
    "title": "Football rankings",
    "markets": 35,
    "contracts": 143983,
    "never_traded": 17
   },
   {
    "series": "ARGDOLLAR",
    "title": "Argentina dollarizes its economy",
    "markets": 2,
    "contracts": 138546,
    "never_traded": 0
   },
   {
    "series": "KXNYCBOROUGHWINBRON",
    "title": "BRONX",
    "markets": 2,
    "contracts": 131141,
    "never_traded": 0
   }
  ]
 }
}