A few months back, I took a look at a number of statistics and problems in the way that they are used in a series called Stat Sheet Misconceptions. A number of these dealt with common statistics for quarterbacks, leading to a discussion about the current passer rating and the problems I have with it. At that time, I didn’t offer a specific alternative, but suggested that pretty much anything would be an improvement.
.
Fast forward a few months to now, and quarterback ratings have come into the spotlight again with ESPN’s new Total Quarterback Rating being released. It definitely is an upgrade over the past system, but because ESPN hasn’t revealed the exact formula for it, it’s been difficult for it to fully catch on. In the time since the our Stat Sheet Misconception pieces ran, we’ve built another alternative to propose one more step in the right direction.
.
Why Another Rating?
You might be wondering … why bother offering a new passer rating when we already have our PFF passing grades and ESPN has put out their new rating? Both are dramatic improvements in evaluating passers and look nothing like the standard that has been in place for way too long. Also, while only ESPN can produce the numbers for their rating, ours is dependent on information found only here at PFF. Conversely, with this effort, we’re aiming to produce a formula that anyone could use – given the right inputs – as an alternative to the standard.
.
.
The Old Formula
While the NFL’s passer rating is a set of complex formulas with upper and lower bounds, in most cases you can ignore them, and the formula simplifies to this.
.
.
The goal in creating the new formula was to maintain a similar structure but introduce values that make more sense. If you interested in why we’re changing parts of the rating, the Stat Sheet Misconception article on passer rating will help. Here we’ll stick with focusing on the changes being made .
.
.
Changing the Inputs
The first Stat Sheet Misconceptions article dealt with completion percentage, and offered a better alternative we called “Accuracy Percentage”. The first step in fixing the Passer Rating formula was to upgrade the Completion Percentage component to PFF’s Accuracy Percentage. With this move, dropped passes, throw aways, and spikes are now accounted for.
.
The second alteration was replacing Yards with “Yards in Air” to reflect the distance that completed passes travel from passer to target. While a quarterback has some effect on yards after the catch, this is difficult to quantify, so we’ve opted to boil it down to the point at which they surely have control.
.
.
Changing the Constants
We eliminated the “+2.083”, because it was simply not needed. To fix the issue of overvaluing touchdowns and interceptions in the old formula, the constants for each were lowered, to 20x for touchdowns and 45x for interceptions. Those values are more consistent with what others have found, and they worked well in this formula too. The last constant-related change was moving the multiplier from 4.16667 to 4.6667; a slight difference, but it adjusts the numbers to be more in line with the look of the old rating.
.
.
The New Formula
Applying it all, here is what we end up with:
.
.
.
Results
Below are 2010’s Top 10 quarterbacks as judged by the new PFF Passer Rating. Also listed are their marks in the old passer rating, and their ranks in each.
.
[table id=202 /]
.
Outside of the Top 10, Colt McCoy’s rank skyrockets from 33rd to 17th, largely due to the facts that 11 of his 222 passes were thrown away and another 18 were dropped. On the flip side, we see both Jon Kitna and Jay Cutler fall eight ranks. Kitna had a relatively very low percentage of his passing yards before the catch, just 42% of his yards were in the air. The new rating helped other QB’s more than it did Cutler in part because he had so few passes dropped.
.
.
Closing Thoughts
While this new formula certainly isn’t perfect, it addresses a lot of the problems from the old rating system and it's a bit easier to calculate than the old rating with no maximums or minimums for each value. To note: it's capable of producing a max rating of 648.67, in which case every attempt would be a 99 yard touchdown with all the yards being in the air … so really there is no maximum.
.
If you asked me what the best method for rating passers is, I would still defer to the PFF pass grades. This exercise has not been about revolutionizing the passer rating but rather offering an improved alternative that deals with the problems from the past.
.
.
Follow Nathan on Twitter: @PFF_NateJahnke and check out our main Twitter feed too: @ProFootbalFocus
.
.
.
.
.
© 2025 PFF - all rights reserved.