March 12, 2023, isn’t just any Sunday. It’s “Selection Sunday,” — the day when the NCAA names the 68 teams that will play in the men’s college basketball tournament, as well as the 68-team field for the women’s tournament.

It’s a day that hoops fans — especially those who gamble — have come to see as a sort of holiday. Anyone who has witnessed March Madness knows there’s a lot of money behind those brackets.

But the extent of the wagering and its legal growth in recent years has turned the annual event into a massive business.

When all is said and done — from office pools and bets with bookies to online gaming — NCAA Tournament time is the focus of billions of dollars in sports wagers.