Here at numberFire, you'll read a lot about Net Expected Points, or NEP for short.

Basically, every single situation on the football field has an expected point value; that is, how many points an average team would be expected to score in that situation (given down, distance-to-go, and yard line). There's a ton of variables -- like down, distance-to-go, and yard line -- but, luckily, numberFire has data from the past decade and a half of every single play, so most situations have come up at least once.

The number of expected points a passer acquires through the air is bottled up into Passing Net Expected Points. Things like turnovers or failed third-down conversions can dramatically decrease a quarterback's Passing NEP, while every time a passer's throw on the field increases the expected point value of the next play, he gets credit for the difference, increasing his overall NEP.

That, in essence, is Net Expected Points.

So with all of this being said, let's take a look at the best quarterbacks seasons of the last dozen years according to the metric.