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As prediction market trading volume booms, Truist analysts say there could be an unlikely source behind the surge.

Analyst Barry Jonas wrote this week that 18- to 20-year-olds, who are too young to gamble legally in most states, could be contributing significantly to the growth of prediction markets.

Specifically, data from HoldCrunch, founded by a former FanDuel executive, shows prediction platform Kalshi is taking more trades on college football than on NFL and NBA. While non-college students could still wager on college results, of course, the trend could offer a clue into the demographics of prediction platform users.

HoldCrunch analyzes the data on an “OSB-equivalent handle” rather than on volumes alone.