The Kentucky Derby just happened this past weekend. It was a big event for horse lovers, of course. But also for gamblers.

Which brings us to a new study from the personal finance website WalletHub that looks at which states have the most addicted gamblers and why. 

People bet on horse races, of course. But in many cases, racetracks are connected to casinos.

In fact, WalletHub said the states with the most gambling addicts all have casinos. Nevada tops the list, followed by:

“South Dakota, Mississippi, Montana and Oklahoma,” said  Jill Gonzalez, an analyst for WalletHub.  

Click the above image to get a by-the-numbers look at the Kentucky Derby.

According to Gonzalez, the states with the most addicted gamblers have two things in common:

“How close you live to a casino, and what are the rules in your state?” she said.

For example, does your state have a lottery?

Click your state below to see where it ranks among WalletHub’s 2016 list of the most gambling-addicted states:

But gambling addiction is hard to measure, especially since millennials don’t like casinos.

“They certainly don’t want to sit there and play in front of slot machines. That doesn’t do anything for them,” said Richard McGowan, a professor of statistics, economics and business policy at Boston College.

But casinos are reaching out to millennials with new machines that let them play against each other.