Recently, Major League Baseball reached a new collective bargaining agreement with the players’ union, avoiding a strike. The changes agreed to within the CBA were largely insignificant to sports fans, but one facet did catch the eye (and ire) of many: the elimination of gifting home field advantage to the winner of the All Star Game.

Major League Baseball returned to organizing its playoff structure in a fashion similar to that of most major sports leagues: the team with the best record gets better seeding and, therefore, home field advantage in the biggest games of the year.

While the Super Bowl is hosted at a neutral site each year, home field advantage is a nevertheless often talked about aspect of NFL games. A balanced regular season schedule and the placement of the Super Bowl at a neutral site means each team plays eight home and eight away games each season to prevent an unfair advantage.

But how much advantage does an NFL team playing at home really have? Let’s crunch the numbers and find out.

As of Week 13, NFL teams playing at home are 110-80-2, good for a winning percentage right around 58. Dialed back to a season’s worth of games, the generic NFL home-team would go 9-7–good enough for a playoff spot most years!

Teams are almost universally better at home, say statistics. In fact, the NFC South is the only division that has a losing record at home, coming in at 11-14. The best, the NFC East, is 18-5. When playoffs are factored in the gap widens, NFL home playoff teams win about two-thirds of their games.

So what plays into this apparent advantage?

For one, the crowd and the noise that naturally comes with it. With tens of thousands of screaming fans surrounding you and your team, communication becomes difficult for away teams and the pressure mounts.

Take, for instance, Centurylink Field, the home of the Seattle Seahawks. The ‘Hawks fans have earned themselves the nickname “the 12th man,” a reference to the fact that 11 people from one team are on a football field at any given time; the fans are then able to act as a 12th and contribute to the team via cheering, booing and so on. And a legacy has certainly been build around the Seahawks fanbase, as their loud screaming during opponent’s offensive possessions makes it difficult for them to communicate, causing false starts, delay of games, and of course enormous pressure to preform well as 70,000 let you know in no uncertain terms that they’d love to see you fail.

Another unheralded facet of home field advantage are the officials at the games. While many fans are quick to blame any given loss on poor penalty calling, statistics show that the home team often has a heavy advantage when it comes to official’s game calling abilities. Chalk it up to loud crowds and, once again, tons of pressure put on those on the field.

Home field advantage is a hotly debated subject across all sports, as many handle the practice slightly differently when it comes to the playoffs. With more modifications surely to come to scheduling and home field advantage in the future, it’s worth considering not just how much it impacts athletes, but why.