Tracking the statistical shifts of each NFL season in real time is always a pretty daunting task.
Every season brings new coaches, new players, new schemes, new stadiums, and new situations to impact those who make decisions that determine the outcome of football games.
Take this year: So far, compared to the whole of last year, passing is up while total offensive plays are down, by quite a big margin.
Already, teams are averaging just 51.2 plays per game, compared to 61.9 last season. Is it because there are more penalties, resulting in lost plays? Are teams letting the clock run out more? Are teams just getting fewer plays in because it's early in the season?
And why does passing the ball, even for young quarterbacks who are supposed to need time to adjust to the NFL, seem to be more successful than ever?
These questions are difficult to untangle, as they are the result of so many variables. But let's try to look at the shape of passing in the NFL this year, and maybe detect why it's continuing to rise.
Percentage-wise, teams are passing just one percentage point more this season versus last. That may seem small, but given the thousands of plays that data is based on, it's a pretty significant jump.
This uptick in passing offense may still seem small overall, but take into consideration that it is occurring during an era in the NFL where passing is already as high as it has ever been.
If you look at the career passing leaders in the rate categories (per game, per season, etc.), it's simple to see there are more successful passers now than ever before.
For example, of the Top 20 career leaders in pass attempts per game, 12 are active, 18 were active through most of this generation, and the other two stopped playing in the late 1990s (Marino and Jim Everett).
Of the Top 10 leaders in career passing yards per game, eight are active, though after that it evens out.
Of the Top 20 leaders in career passer rating, 14 are active, two (Trent Green and Jeff Garcia) just stopped playing, and the rest, with the exception of Otto Graham, played pretty late into the 1990s.
It's been a passer's paradise the last decade, but, the way it's shaping up this year, that's been true more than ever.
Even compared to just the last few years, it's easy to see that even if passing isn't necessarily becoming more frequent, it is becoming safer and, thus, a more attractive option for teams.
Let's just compare these stats (via Pro Football Reference) from just the last four years, and see if you can spot the trends:
Interceptions per game: 2006: 1.0; 2007: 1.0; 2008: 0.9; 2009: 0.7;
Percentage of pass attempts intercepted: 2006: 3.2; 2007: 3.1; 2008: 2.8; 2009: 2.6;
Sacks per game: 2006: 2.3; 2007: 2.2; 2008; 2.0; 2009: 1.8;
League Average QB Rating: 2006: 78.5; 2007: 80.9; 2008: 81.5; 2009: 82.5;
20+ yard completions per pass attempt: 2006: 8.4%; 2007: 7.9%; 2008: 8.2%; 2009: 9.5%;
40+ yard completions per pass attempt: 2006: 1.6%; 2007: 1.4%; 1008: 1.5%; 2009: 1.7%;
Now I may be hallucinating from the 20 proof cough syrup flowing through my veins right now, but I'd say that's some pretty telling evidence that pass plays are dominating the NFL more and more.
Basically what I'm getting at, is that teams are passing about the same (and at about the same completion percentage and yards per attempt) rate, but are becoming more successful, as a whole, in executing their passing offense.
The last two lines above are most telling, to me. Most people might look at the reduction in interceptions and assume, as I first did, that teams are simply calling safer pass plays such as slants, comebacks, curls, outs, screens, etc.
And yet, on average, teams are completing more of their passes further downfield, year after year—especially this year.
Why is this? Well, I'd say that we're experiencing a generational overlap, where the next generation of quality young quarterbacks is stepping into their own, while the previous generation continues to be successful.
Even in the last few years, there has been an influx of quality (or at least dependable) passers in the NFL.
When you add in the solid production of young guys like Joe Flacco, Matt Ryan, Jay Cutler, and Jason Campbell to those who just preceded them (Ben Roethlisberger, Philip Rivers, Eli Manning, Tony Romo, Matt Schaub, Carson Palmer) and those who have been in the league awhile (McNabb, Brees, Brady, Manning, etc.), you find that there are a surprising number of effective quarterbacks in the league right now, and that number has been growing steadily.
Now this isn't to say that it's all down to suddenly tremendous quarterback play. The league has continued to insulate pass production through a variety of rule changes that both allow receivers greater freedom downfield, and offer greater protection for the quarterback in the pocket.
In fact, I'd also point out that it is those rules, as much as anything, that are allowing young quarterbacks to cope with the increased speed and pressure of the NFL game, leading to this overlap.
You see it every weekend: A defensive end tries to spin around a lineman, and inadvertently hits a quarterback's helmet, catching a flag for his trouble.
The rules in place, and the way they're being interpreted by NFL referees, are forcing teams to be less aggressive in their pursuit of quarterbacks, resulting in less effective defense overall.
It's surprising, too, because defense in the NFL has also changed quite a bit in the last few years.
Specifically, more and more teams have switched to a 3-4 alignment, which allows their most athletic pass rushers, generally linebackers, to get at the quarterback.
Even looking at the individual sack numbers, it's pretty easy to see that teams are getting better at exploiting one-on-one matchups to let their best players attack the quarterback, especially from the 3-4.
Yet still, passing continues to become a more effective method of moving the ball.
Overall, there's no single great strategy in the NFL, no single path to success, and I recognize that I'm drawing with pretty broad strokes here.
There are undefeated teams that run more than 50 percent of the time (the Giants and Saints), there are undefeated teams that run less than 40 percent of the time (The Colts).
The team that may set the all-time single season mark in pass attempts (the Patriots) is a rather unconvincing 3-2 after five games, and a paltry 3.6 yards per carry average.
Simply put, there are a lot of ways to win football games.
Still, the general shape of NFL offenses in 2009 indicates that passing has become safer than ever, and that defenses are struggling to create pressure in the face of new rule changes.
Will that keep up the rest of the year? Who knows? But it's certainly an interesting development so far.