— Aaron Rodgers is currently the NFL’s all-time career leader in passer rating, a fact that should leave you impressed, baffled, and maybe a little insulted.
Rodgers’ career passer rating is 98.4. Super Bowl foe Ben Roethlisberger ranks eighth on the all-time list at 92.5. The players between them, in order: Philip Rivers, Steve Young, Tony Romo, Tom Brady, Peyton Manning, and Kurt Warner. Some nobody named “Joe Montana” comes in ninth, with Drew Brees rounding out the top 10.
Rodgers is a very good quarterback, but unless you are wearing a cheesehead while reading this, you aren’t going to rank him above Brady, Manning, or Brees among modern starters, let alone above all-time greats like Montana or Roger Staubach (31st, below .. shudder … Matt Cassel). But there's Rodgers, sitting atop the closest thing the NFL has to an “official” index of quarterback quality.
The NFL’s passer rating is a little bit like your credit rating: You know it’s important, you know that “higher” means “better,” and you have some vague idea of how it’s calculated. But it’s still mysterious, overcomplicated, and a little suspicious. Will those two missed credit card payments in 1993 really keep me from leasing this car? Did that screen pass to John Kuhn really move Rodgers past Joe Montana?
To find out how Rodgers reached the top of the heap, we need to take a close look at how the passer rating works and why it’s flawed.
Football and slide rules
The NFL spent decades searching for the best statistic for ranking quarterbacks and selecting an official passing leader. The league ranked quarterbacks by passing yards, yards-per-attempt, touchdowns, and completion percentage, but no matter what stat they used, the results always came out flaky. Inevitably, the completion percentage leader was a part-time starter who barely threw enough passes to qualify, or the yardage leader a mad bomber for a terrible team forever playing catch-up.
The “best” quarterback — Johnny Unitas or Bart Starr — typically did a lot of things well, but not well enough to lead the league in any one category.
So the NFL decided they needed a new statistic, and the league formed a committee. That’s what the passer rating is — a stat developed by a committee. A committee that met in the early 1970s, when pocket calculators were the size of blimps.
The committee took four pretty good measures of quarterback quality — completion percentage, yards per attempt, touchdown percentage, and interception percentage — macerated them beyond recognition, then threw them in the slow-cooker until they boiled down into a numerical gruel. They then plated the results and served them to an unquestioning public.
The Wikipedia entry on the passer rating shows the algebra involved. No one in their right minds actually calculates the rating by hand anymore; we use spreadsheets or handy on-line calculators. (Here’s one you can use to determine your child’s Pop Warner rating). In the old days, statisticians used actuarial tables and slide rules to help with all of the decimals and division; ranking quarterbacks and calculating mortgages required the exact same skill set.
So what does all of that Algebra mean? Those formulas take familiar stats like completion percentage, weigh them so they can be compared to one another, then adjust them according to league averages.
The mathematical juggling hides two major flaws.
First, it’s an insanely over-engineered solution to a simple problem, but we’ve come to expect that from a league that can turn a simple concept like a “fumble” into Supreme Court-worthy legislation. Second, the rating compares quarterbacks to an “average” that was established in 1970, which might as well have been the Stone Age.
Muscle cars and quarterbacks
Quarterbacks of the 1960s and 1970s were like automobiles from the same era. They were awesome in many ways, but they were also inefficient and a little primitive.
In 1970, when the passer rating was in committee, the league completion percentage was 51 percent. It now hovers around 60 percent. Average quarterbacks in 1970 threw 28 percent more interceptions than touchdowns. Now, they throw about 21 percent fewer interceptions than touchdowns. In 1970, Bob Griese completed 58 percent of his passes and threw for 12 touchdowns and 17 interceptions. He led the Dolphins to a 10-4 record, made the Pro Bowl, and developed into a Hall of Famer. Alex Smith and Donovan McNabb put up similar (slightly better) numbers this season, and both lost their jobs.
NFL rules and strategies were very different in 1970. Cornerbacks could hold, but left tackles couldn’t. There were no empty backfield formations or tunnel screens to wide receivers. Quarterbacks threw less often, but the passes they did attempt were generally longer. The passer rating did a fine job selecting the best quarterback in the NFL in the context of the 1970s, rewarding efficient passers like Griese and Staubach over guys who just threw a lot.
Innovations like the West Coast Offense and the pass-friendly 1978 rules changes soon made the 1970 “averages” obsolete. Unfortunately, those averages are hard-wired into the rating formula. So the passer rating formula sees a quarterback with a 56 percent completion rate who averages an interception per game — a clearly “below average” quarterback — and rates him as above average in multiple categories! And when it’s fed Rodgers’ numbers, with completion percentages around 64 percent and very low interception rates, the formula practically short circuits.
Comparing Rodgers to someone like Staubach is like comparing a 2011 Honda Accord to a 1970 Chevelle. Both are great cars in their own way. But use 1970s criteria to evaluate the cars, and the Accord, with it’s mileage and modern technology, would blast the Chevelle off the track. The results would tell you little about the cars, but a lot about the out-of-date method of ranking them.
The Iceberg Factor
OK, that explains why Rodgers outranks Staubach, or even Montana. How the heck does he outrank Brady, Manning, and Brees?
The passer rating is built exclusively from percentage stats, not raw totals. Percentage stats can go up and down during a quarterback’s career. As you know, quarterbacks usually play poorly as rookies, improve until they peak for a few seasons, then (if they are very good) hang around for a few seasons as their performance and statistics decline. A quarterback’s lifetime passer rating accounts for all three phases of his career: rise, peak, fall.
Now, look at Rodgers’ career. It’s all peak. He spent his “rise” throwing 59 passes in three years while waiting for Brett Favre to cut bait. He hasn’t had time to fall yet.
Rivers, second all-time, shares a similar resume. He spent two seasons behind Drew Brees instead of throwing stat-deflating interceptions. Romo (third) hung around the bench for several seasons and was more-or-less at his peak the moment he stepped on the field. Call it the “Iceberg” Theory: Active quarterbacks often reach the top of the passer rating list because we only see the tip of their iceberg.
As quarterbacks age, the law of averages starts to temper their statistics, which is why Brady, Manning, Roethlisberger and Brees have slipped below the newcomers. Brady and Manning will probably wind up like Young and Montana, hovering at the top of the list forever, but always wedged among a bunch of young guns coming off two or three hot seasons. They deserve better. The league should raise the minimum pass attempt requirement for the career rating list from 1,500 passes to 2,500. That would cut our Rodgers Romo, and Rivers for at least another season, forcing them to prove a little more before they sneak into a club that’s too exclusive for them.
Ironically, Rodgers’ high passer rating could be held against him. When television announcers use graphics to show that Rodgers has the highest rating in history, it forces viewers to be skeptical. If Rodgers ranks as the best ever at some bogus stat, maybe there’s something bogus about his performance. Maybe it's too many screens, too much reliance on his receivers, something inherently “wimpy” about completing five-yard smashes to Greg Jennings when every Staubach pass was an 80-yard bomb into the Steel Curtain.
Rodgers is an excellent quarterback, just achieving his potential. He doesn’t need a glitch antique statistic to make him into something more. As for the passer rating itself, think of it as a grandfather: Old fashioned, set in its ways, and a little silly, but still worth listening to, if only to understand how quickly times have changed.