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For more from Chase and Jason, check out their work at Football Perspective and The Big Lead.

Tony Romo’s career stats aren’t as misleading as I thought

Posted by Chase Stuart on August 23, 2010

If you go to PFR's leaderboard page, you can see that Tony Romo ranks 4th all time in yards per pass attempt, and all three quarterbacks ahead of him retired by 1960. Romo also ranks first in net yards per attempt (PFR has NY/A data beginning in 1969, which is the earliest year for which we have complete individual sack data) and first in adjusted net yards per attempt among all players. You can use PFR-'s play index to see a list of the top active quarterbacks in yards per attempt, and I've heard multiple sources cite Romo's incredible career average in that category.

My initial take when I heard such propaganda was that is was incredibly misleading. Why?

1) Romo obviously plays in a much more pass-friendly era than nearly every quarterback in league history.
2) Romo, because he was an undrafted free agent, didn't see the field during his early years. Young quarterbacks tend to play poorly, and sitting on the bench during your first couple of years will help boost your career averages, especially when you have only played for a few seasons. Which brings me to ...
3) Romo just turned 30 years old in April; he hasn't yet played during the final years of his career, when most quarterbacks tend to kill their career averages. For example, the Patriots Steve Grogan retired with a career yards per attempt average of 7.48, but from age 25 to 34, Grogan averaged 7.98 yards per attempt. Romo, unless he retires early, will sink his career averages at least a little bit by the end of his career.

Sure, the player season finder tells us that Romo's 8.10 yards per attempt average is the fourth best ever, but we know that is really misleading. What we need to do is adjust for those three factors isolated above. And, in fact, that's really easy to do. We can use the player season finder to only look at quarterback seasons at ages 26, 27, 28 and 29 -- Romo has never thrown a pass at any other age.

Figuring out a cut-off is a matter of preference, but the results don't change too significantly here. If we require only 600 pass attempts over those four seasons, Romo still ranks 7th all-time; raising the cut-off to 900 attempts (Romo has 1,857) brings Romo back into 4th place, albeit in a tie with Bart Starr.

Okay, but what about adjusting for era? Last July, Doug introduced the Advanced Passing tables to PFR. He wrote:

In each of nine different passing rate stats, we have computed each player's standard deviations above (or below) league average for that season and converted it to an "IQ score" (average = 100, standard deviation = 15). From the glossary:

  • On all stats, 100 is league average.
  • On all stats (including sack percentage and interception percentage), a higher number means better than average
  • The greatest passing seasons of all time are in the 140s. A typical league-leading season in most categories will be in the high 120s or the low-to-mid 130s.

The advanced passing stats (represented by acronyms like Y/A+) are loaded into the player season finder, which makes this a simple exercise. And, according to that tool, where does Romo rank? With a cut-off of 600 attempts, Romo is in a four-way tie for 5th place in league history. If we use 900 attempts as the cut-off, Romo is in a three-way tie for 2nd place, all-time in Y/A+ by quarterbacks between the ages of 26 and 29. Romo does drop into a tie with Joe Namath for 8th place since 1969 by a quarterback between those ages in ANY/A+ (which is why Jason thinks that Namath is a legit, HOF quarterback).

One reason Romo still looks good when we adjust for era? It may be a passer friendly era in terms of pass attempts, sack rates, and interception rates, but yards per attempt numbers aren't nearly as inflated as you might think. This page breaks down all passing numbers per team game for each season in NFL history. Let's break it down by decade:

	Y/A	Att	INT%	TD%	Sk%	ANY/A
2000s	6.83	32.7	3.16	4.05	6.47	5.40
1990s	6.79	32.4	3.36	3.93	6.85	5.21
1980s	7.04	31.7	4.18	4.2	7.54	4.98
1970s	6.67	26.2	5.26	4.18	8.20	4.04
1960s	7.26	27.7	5.59	5.26	8.68	4.60
1950s	6.95	26.7	7.01	5.04	8.05	3.78

There's no doubt that Romo and other modern passers enjoy several advantages when it comes to putting up good numbers relative to passers from the '60s and '70s. First, they play in two more games a season. Then, they pass the ball significantly more frequently in each game. And they get sacked less often and throw fewer interceptions -- both due to rule changes in the sport, not because today's quarterbacks are better at what they do. As a result, modern quarterbacks tend to look excellent in terms of gross passing stats and ANY/A relative to their forefathers. Completion percentages, not shown above, are subject to perhaps the largest era bias of all the major stats.

On the other hand, vanilla average yards per pass attempt hasn't changed all that much. For the most part, the league average has always been around 7.0 yards per attempt. And that's why Romo's numbers don't necessarily need to be adjusted for era, at least when you're talking about yards per pass. Adjusting for era and age, Romo's Y/A+ shows that he was only bested by one man -- Otto Graham, who spent all four seasons playing in the AAFC, and not the NFL, during those ages.

If you want to move past the Y/A stats, Romo still is in elite company when it comes to ANY/A. For the 41 years where we have ANY/A data, look at which quarterbacks rank in the top ten during ages 26 to 29: Five Hall of Fame quarterbacks (Montana, Fouts, Aikman, Namath and Marino), two future HOF QBs (Manning and Favre), another guy who could be on the HOF path (Rivers) and Mark Rypien. For quarterbacks, winning the Super Bowl has become inextricably tied with being considered a successful quarterback. But Romo has been about as good as you could ask for if you're a Cowboys fan, and he may be in for his biggest season yet in 2010. In addition to having what looks to be an incredibly stacked offense, Romo's Cowboys would be set up nicely to win the Super Bowl this year, played at Jerry World.

This entry was posted on Monday, August 23rd, 2010 at 6:49 am and is filed under History, Play Index. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.