In 2015, Americans bet $149 billion illegally on sporting events.

Today’s infographic from Longitude breaks down America’s multi-billion dollar sports betting industry. It shows the four states where fixed odds betting through bookmakers is legal, and it also compares a more legal alternative that’s available in 43 states.

(Click on image to enlarge)

The sports betting industry

Sports betting is a thriving underground business. A recent example of this is Super Bowl 50, which is estimated to have fetched a record-breaking $4.1 billion in illegal bets. Only an additional $100 million of bets, or 3% of the total, were made legally.

But what’s the difference between a legal bet, and an underground one? It all depends on where you live and how the betting is done.

Fixed-odds betting, in which odds are created by a bookmaker, is legal in just four states: Montana, Oregon, Delaware, and of course Nevada.

Pari-mutuel wagering, which instead pools players bets together to calculate odds, is legal in 43 states. Pari-mutuel payout odds depend on the amount of bets, and generate transparent profits because of fixed commission fees paid to the operator.

The US horse racing industry already uses pari-mutuel wagering, and it generates a range of economic benefits. This includes $102 billion in economic benefits generated annually and the support of 1.2 million jobs across the country.