If you paid attention in high school economics, you already know the theory of supply and demand: the more of something there are, the less value they have. Seems the same thing applies to dating, because new research shows men are more likely to spend money on a woman if he thinks she’s his one shot at … well, let’s call it “romantic opportunity.” Or sex. We can call it sex. You’re so boring though.

The University of Minnesota’s Vladis Griskevicius did a study that found sex ratio — or how many men there are compared to the number of available women — directly impacts economic decisions like how much the guy is willing to save, spend and borrow.

In other words, the fewer women there are, the less likely men care about saving for the future, making them more willing to spend impulsively and even take on more debt. Why? Because they believe they have to spend more money to get the girl.

Whether or not that’s true is for you to decide, but just remember that even though he’s often the only guy in the Playboy Mansion, Hugh Hefner is still known for being quite generous — and he always has a gorgeous girl (or six) on his arm.