The NFL has long had their passer rating metric, which has come under criticism from some quarters in recent years.  The passer rating, of course, is a number we can use to compare quarterbacks to one another.  It takes into account completions, attempts, yardage, touchdowns, and interceptions.  The formula is a little bit complicated, but it’s fairly straight forward to implement in a spreadsheet or (as I have done in the past) in javascript.  I won’t go into the details of the formula hear, but if you want to know the nitty gritty details, there’s a nice article on it on wikipedia.

The passer rating metric is far from perfect, but I think it’s a terrific resource, despite it’s flaws.  Let’s consider some of the flaws: 1) It doesn’t take into account when a quarterback runs for a 1st down; 2) It doesn’t take into account when the quarterback takes a sack instead of throwing the ball away (in fact, throwing the ball away would actually hurt the passer rating while taking a sack would not); 3) It doesn’t take into account when the quarterback fumbles the ball; 4) It doesn’t take into account yards after the catch (for example, the quarterback might make a little 5 yard pass and the receiver breaks 7 tackles on the way to an 80 yard touchdown); and 5) One might reasonably quibble with the formula and the weight it gives to the various factors it does take into consideration (for example, is completion percentage more important than TD:INT ratios, and if so, or if not, what should the relative weighting be?).  This is just to name a few criticisms right off the top of my formerly fully haired head.

But the real question for me is, does this passer rating metric correlate to wins and losses?  It’s all well and good for a quarterback to have a high passer rating, but if his record as a starter is 1-10, that’s not good.  And vice versa for the quarterback who doesn’t have a great passer rating, and yet he finds a way to win the games.

Passer ratings work both ways.  You can have an offensive passer rating (your quarterback) and a defensive passer rating (cumulative passer rating of all of your opponents’ quarterbacks).  That latter defensive passer rating (in my humble opinion) is one of the more underrated stats that often goes ignored.  Typically when one of the talking heads says this is the “top rated defense” or the “best defense” in the league he’s referring to that total yardage allowed stat.  Remember 2009?  That was the year the New Orleans Football Saints won the Superbowl.  Going into that Superbowl game a lot of media experts pointed to that 25th ranking the Saints defense had in total yardage, but they ignored the #3 ranking they had in opponent passer rating.  They said the Saints had been “lucky” with all the turnovers they’d been getting that year, but the luck would run out against the living legend, Peyton Manning.  (See my twitter background pic featuring Tracy Porter celebrating his pick 6 with Manning propped up on one elbow watching.)  The Saints that year allowed 15 passing TD’s while collecting 26 INT’s.  But enough reminiscing…

So, what I’ve done is come up with what I’m calling a “net passer rating”.  This is simple enough.  It’s your team’s offensive passer rating minus its opponents’ cumulative passer rating in those games they played against your team.  In other words it’s passer rating – opp. passer rating.  Here is a table of results for the 2016 season, sorted by net passer rating:

Team net passer rating winning percentage passer rating opponent passer rating
New England Patriots 25.1 0.875 109.5 84.4
Atlanta Falcons 24.3 0.688 116.8 92.5
Minnesota Vikings 14.7 0.5 97.7 83
Denver Broncos 14.2 0.563 83.9 69.7
Kansas City Chiefs 13.4 0.75 93.2 79.8
New York Giants 10.2 0.688 86 75.8
Dallas Cowboys 8.9 0.813 103 94.1
Cincinnati Bengals 8.7 0.406 91.8 83.1
Seattle Seahawks 8.4 0.656 93.4 85
Miami Dolphins 7 0.625 95.5 88.5
Pittsburgh Steelers 6.6 0.688 93.9 87.3
Green Bay Packers 6.4 0.625 102.3 95.9
Washington Redskins 6.3 0.531 97.4 91.1
Oakland Raiders 5.5 0.75 95.3 89.8
Tennessee Titans 5.4 0.563 93.7 88.3
New Orleans Saints 4.4 0.438 102.5 98.1
San Diego Chargers 3.8 0.313 87.6 83.8
Buffalo Bills 0.8 0.438 86.7 85.9
Arizona Cardinals -1.6 0.469 83.5 85.1
Tampa Bay Buccaneers -1.8 0.563 87 88.8
Indianapolis Colts -3 0.5 94.5 97.5
Baltimore Ravens -4.3 0.5 82.6 86.9
Philadelphia Eagles -6.5 0.438 79.2 85.7
Jacksonville Jaguars -9 0.188 79.5 88.5
Houston Texans -11 0.563 73.3 84.3
Chicago Bears -11.7 0.188 81.8 93.5
Detroit Lions -13.2 0.563 93.3 106.5
San Francisco 49ers -13.5 0.125 83.4 96.9
Carolina Panthers -16.9 0.375 75.1 92
Cleveland Browns -24.4 0.063 77.4 101.8
Los Angeles Rams -26 0.25 69.5 95.5
New York Jets -30.9 0.313 67.6 98.5

You will notice the top 2 teams were the 2 teams in the Superbowl last year and the bottom few teams were the Jets, Rams, and Browns.  Need I say more?  Probably, but you know I will.

There were 18 teams with a positive net passer rating, and only 4 of the 18 had a losing record.  Of the 14 teams with a negative net passer rating only 3 had a winning record.  In other words, about 78.13% of the time the net passer rating directly correlates to the team’s record (positive net passer rating = winning record, negative net passer rating = losing record).  In the following chart you can see how net passer rating correlates to wins over .500 (or under .500):

NFL net passer rating chart

If the blue line is above zero it means a positive net passer rating.  The orange represents the number of wins (relative to 8 wins) the team had.  So, if the orange is below zero it means the team had fewer than 8 wins.

In summary, the net passer rating strongly correlates to winning and losing, but there are certainly other factors.  For example, the running game, fumbles, special teams, etc.  The Saints were one of the four teams with a positive net passer rating and yet a losing record.  You will no doubt recall 3 blocked kicks that were run back for scores (actually, one was stopped short of the end zone, but the opponent ended up deep in Saints territory and scored either on the next play or the one after that).  There were some fumbles that were returned for scores, too, as I recall (try as a might to forget).  And there were a few, let’s just say, “borderline” calls by the officials, many of which went against the Saints.  No excuses, though.  You have to be good enough to overcome those things, and the Saints, frankly, weren’t.  But hope springs eternal, and the Saints will rebound in 2017.  Believe dat!

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