As recently as 10 or 20 years ago, oddsmakers didn't have very much information on teams at their disposal. Sure, they could scrape together stats based on box scores and such. But they couldn't figure out the average 40-yard dash times of two teams simply by pressing a couple of buttons. Today, they can look up just about anything—and we do mean anything—in the blink of an eye in order to help them compare and evaluate teams. So while things like records and the weather still play a large role in the betting lines that are set, oddsmakers are now able to use advanced statistics in order to pinpoint exactly how many points Team A should beat Team B by. And it's actually kind of scary to see how close they usually come to being right.