Statistics can be used to say a lot of things about the National Football League, and most of them can be slanted in any number of ways. However, there is one stat that, though it doesn’t seem to be discussed frequently, has become known as the “Mother of All Stats,” and it has a very high correlation to postseason success in the NFL.

And, for the Minnesota Vikings, this is a very good thing.

The statistic that I’m talking about is one called Passer Rating Differential. It’s a very simple statistic to calculate. You simply take a team’s passer rating and subtract the passer rating that their defense allowed. The difference between those two numbers is the Passer Rating Differential.

According to the folks from Cold, Hard Football Facts, the Vikings are #1 in the league in this particular statistic for the 2017 season. The Vikings had a team passer rating of 99.09, and had a passer rating allowed of 73.02. That gives them a Passer Rating Differential of 26.07, which is the league’s best.

How much of an indicator has this stat been over the years? Well, according to CHFF, from 1940 to 2016:

Approximately 36% of all NFL champions since 1940 have ranked #1 in the league in this stat

60% have ranked in the top three

95% have ranked in the top ten

Four of the top five teams in PRD this season were NFC teams, with the Vikings at #1, two of their potential Divisional Round opponents, the New Orleans Saints and the Los Angeles Rams, at #2 and #3, respectively, and the Philadelphia Eagles at #5. The Eagles’ rating is a bit misleading at this point, as it was largely a function of the play of Carson Wentz for much of the season, and he’s now on injured reserve.

Here are the PRD figures for every team in this year’s postseason:

Vikings: 26.07 (#1 in NFL) Saints: 24.86 (#2) Rams: 19.99 (#3) Chiefs: 19.26 (#4) Eagles: 18.11 (#5) Jaguars: 15.93 (#7) Patriots: 13.07 (#10) Steelers: 12.31 (#12) Bills: 3.24 (#14) Falcons: 0.45 (#16) Titans: -10.62 (#21) Panthers: -13.16 (#24)

Now, obviously this doesn’t automatically mean that the Minnesota Vikings are going to be hoisting a big, silver trophy on their home field on the first Sunday in February. However, it’s a potential indicator, and one that points very favorably in the direction of the purple.