Is This the Most Explosive Era of Offense in NFL History?

We are living through the most mind-blowing era of offensive production the NFL has ever seen.

Teams are passing and scoring at rates that are insane, bonkers—bananas, even.

Thanks to today's pass-first (and -second, and -third) play-calling, multi-receiver sets, shotgun snaps and hurry-up tempos, offensive numbers are blowing up.

Detroit Lions quarterback Matthew Stafford is on pace to throw for 5,440 yards this season. If he does, he'll break the NFL single-season passing-yardage record, last broken in 2011—when Dan Marino's mark of 5,084 yards was finally toppled after 27 years.

Stafford's on pace to finish his fifth season with staggering career numbers: 1,524 completions, 2,508 attempts, 18,247 yards and 112 touchdowns—the first three of which would be Detroit Lions franchise records.

Think about what those numbers might be if he hadn't missed 19 games of his young career due to injury.

After just 60 projected starts, Stafford's career numbers will be comparable to those of legends like Daryle "The Mad Bomber" Lamonica. Lamonica had 88 career starts in 12 seasons but only compiled 1,288 completions, 2,601 attempts, 19,154 yards and 164 touchdowns.

You haven't even heard the craziest part: Three quarterbacks have thrown for more yards this season than Stafford.

In fact, five players are on pace to top Marino's old record this season. Just three years after Marino was knocked out of the top spot, he may be relegated to ninth place.

Per Pro-Football-Reference, seven of the top 10 passing seasons of all time have occurred in the past two years, and seven or eight quarterbacks this season have a legitimate shot at cracking the list.

Over the broad sweep of 94 NFL seasons, only 37 quarterbacks have over 30,000 career passing yards—and six (16.2 percent) of them are starting this weekend.

The NFL as a whole is averaging 22.6 points per game this season, on pace to be tied for the fifth-highest-scoring season ever. 2012 is the fourth-highest-scoring of all time. 2011 is eighth-highest. 2010 and 2008 are tied for ninth.

With unprecedented amounts of passing leading to all-time highs in offensive output, is this the most explosive era of offense in NFL history?

Offensive Output

Let's look at how teams have scored across NFL history. This graph shows the NFL's league-wide average points scored per game for each season since 1950:

The thick blue line represents the actual figures, while the thin red line is the four-year moving average. As you can see, scoring dropped steadily until 1958, then bounced back and trended upward. In the late 1960s, scoring steeply declined, bottoming out in 1977 when teams averaged just 17.2 points per game.

On average, each NFL team scored 5.9 points (a touchdown!) less per game in 1977 than 1965. That's a stunning 25.5 percent drop in scoring over a 13-year span.

Scoring then climbed steadily upward to a mid-to-late 1980s peak, then dipped back down until 1993, when it bottomed out at 18.7 points per game. Offense has been on the rise ever since; in 2012, NFL teams averaged 22.8 points per game, the fourth-highest rate of all time.

That's a 4.1 point-per-game boost from 1993 to 2012—or, put another way, a 21.9 percent rise in scoring over 20 seasons.

The field hasn't changed size, and they've always played 60 minutes of football. What caused these massive swings in production? Is it fast-paced passing offenses replacing plodding running offenses?

As it turns out, not really.

In Philadelphia Eagles head coach Chip Kelly's massively hyped hurry-up offense, the revved-up tempo is supposed to give the Eagles offense an advantage by taking extra bites of the defensive apple.

After three games, per Pro-Football-Reference, the Eagles are averaging 66 plays per game. The NFL average through three games is 65.7. From 1950 to today, the league average of plays per game has never risen above 67.3 (1950) or fallen below 59.9 (1992).

As the chart shows, the league stayed very close to that bottom figure through much of the 1960s and from 1990 to 1993. There's been a 6.1-percent boost from 2008 to today—which is a significant trend but well within the typical mid-60s range.

The average amount of yards gained per game has been more volatile, but not much. From 1977 on, save for a dip in the early '90s, NFL offenses have steadily gained more and more yards per game, despite plays per game remaining relatively stable.

Since the recent low point of 1992, offensive yardage is up 55.7 yards per game, or 18.7 percent.

Clearly, something (or some things) happened in 1978 and 1994 that reversed strong downward trends in offense. What could they be?

The 1978 Rules Changes

In 1978, the NFL made a series of rule changes designed specifically to open up the passing game and increase scoring.

Included among these was the "Mel Blount Rule," named after the physical Pittsburgh Steelers Hall of Fame cornerback. Contact with receivers was prohibited beyond five yards past the line of scrimmage. 

Less famously, but no less importantly, offensive linemen were permitted to pass-block with extended arms and open hands.

The changes worked, to great effect. NFL Films tabbed these changes No. 7 in their "Top Ten Things that Changed the Game" video (which is definitely worth watching).

Let's look at how the run/pass balance has evolved over the decades:

First, let's look at the darker pair of lines: the league average number of rushing and passing attempts per game by year.

Before the 1978 rules changes, NFL teams always ran more often than they passed. That split was as wide as 60.7-percent run to 36.5-percent pass in 1956 and as narrow as 51.6-percent run to 48.4-percent pass in 1966, but it was always run over pass.

League-wide average pass attempts per game skyrocketed from 25 in 1977 to 31.7 in 1981, an increase of 26.8 percent. Don "Air" Coryell, head coach of the San Diego Chargers, implemented an aggressive, pass-heavy offense that thrived during this period, leading the NFL in offensive yards from 1980 to 1983.

Bill Walsh took over the San Francisco 49ers in 1979, and his combination of power running and short, timing pass routes revolutionized the game. Coryell, himself inspired by legendary Chargers coach Sid Gillman, and Walsh, a disciple of the legendary Paul Brown, are the progenitors of the two most influential "coaching trees" in football.

We see their influence in the lighter pair of bars, the "first downs by rushing" and "first downs by passing." Until the 1978 rule changes, the rate at which teams got first downs by rushing or passing was much, much closer than the frequency with which they rushed or passed.

During the 1960s, when run/pass balance was nearly at equilibrium, teams steadily picked up about seven first downs a game on the ground and about nine through the air. Before and after that, teams ran much more often than they passed but moved the chains just as frequently passing the ball.

After the rule changes, passing first downs jumped from just under eight per game to just over 10, where they would stay (save for a 1994-95 bump) until 2008.

Since 2008, the average number of passing first downs per game has climbed from 10.8 to 12.7, a 17.6-percent increase.

Rushing first downs began a very, very slow decline from an average of 7.7 per game in 1978 to 5.6 this season, a 27.3-percent decrease.

Despite this explosion in chain-moving effectiveness, passing attempts stayed consistent for most of the 1980s, until a dip at the tail end that bottomed out at 29.9 in 1992. Meanwhile, rushing attempts fell off steadily from 1977 to 1992. They dropped from 37.4 carries per game to 27.4, a 26.7-percent decline.

OK, so what happened in the mid-'90s?

The 1994 Rule Change

It doesn't get as much press as the 1978 changes, but there was a seemingly minor rule change that had a drastic, immediate effect on scoring: The NFL moved the kickoff back from the 35-yard line to the 30-yard line.

How could five yards make any kind of difference? Well, when touchbacks become returns and returns become longer returns, it has a huge impact on starting field position. Let's look at that points-per-game chart again:

From 1993 to 1994, there was a 1.6 point-per-game increase in scoring. That may not sound like much, but it's a boost of 8.5 percent. From 1993 to 1995, the increase was 2.8 points (a field goal for each team, every game!), a 15-percent increase in scoring.

Fifteen percent! In two years!

It was like the six-year offensive decline from 1987 to 1993 never happened. Scoring was up-and-down for a few years after that but steadily trended upward toward all-time highs. Since 2009, scoring has gone up every single season (though 2013, through three games, is lagging slightly behind 2012).

The Shotgun Revolution

Unlike the rule changes of 1978, moving the kickoff five yards deeper didn't have any kind of lasting impact. It didn't open up possibilities for revolutionary new offensive systems. It just gave offenses a quick shot in the arm.

But scoring, yards and plays have all trended strongly upward over the last decade.

Much of the recent increase in offensive yardage has come from 2005 to 2013. Since 2005, offensive yardage has risen every single year, up 12 percent and climbing.

I wrote about it earlier this summer; the trends over the last 10 years have been unmistakable:

What's fueling all of this?

The shotgun formation.

Walsh and Coryell weren't afraid to deploy slot receivers, running backs or tight ends as passing weapons. Players like tailback Roger Craig, receiver Charlie Joiner and tight ends Kellen Winslow Sr. and Brent Jones helped redefine their positions as integral parts of the passing game.

Versatile, multidimensional players created headaches for defenses of the day. Those coaches rarely sent out three receivers, a pass-catching tight end and a running back all out for a pass at the same time, though.

Despite a brief flirtation with the four-receiver run-and-shoot in the late 1980s and early 1990s, NFL coaches were still too preoccupied with the run game to be that diversified in the passing game.

Worse, NFL defenses were beginning to attack quarterbacks with aggressive blitzing schemes. You can't protect a quarterback taking five- and seven-step drops against six rushers with an empty backfield...hence, the shotgun.

With the shotgun, quarterbacks have much more time and space to make their pre- and post-snap reads, diagnose blitzes and coverages, and make better decisions. It also gives offensive coordinators the ability to explore all kinds of new formations, alignments, wrinkles and route packages that get receivers open quickly—so quarterbacks can get rid of it before the rush gets to them.

All of these innovations have made passing not only much more effective than running, but also no less safe than running.

Have you ever heard the old adage, "Three things can happen when you throw the ball, and two of them are bad"? Well, there used to be a lot more truth to it. Let's look at NFL passing risk and reward from 1932 to today:

The blue line, completion percentage, is mapped on a secondary axis (the blue numbers on the right), but the red and green lines, interception percentage and touchdown percentage, respectively, are mapped to the primary axis (the black numbers on the right).

In 1933, the average NFL pass completion rate was 35.7 percent. The average touchdown rate was 3.5 percent. The average interception rate was—and I do hope you're sitting down—15.4 percent.

Imagine an NFL where there was practically a 50/50 chance that every pass thrown was caught by the wrong team, and you can understand why old-school football coaches were hesitant to let it fly.

By 1943, though, vertical possibilities were being explored, and the average NFL passing touchdown rate hit an all-time high of 6.5 percent. The average interception rate that season was a relatively manageable 10.6 percent—in the ballpark of Jacksonville Jaguars rookie wide receiver Denard Robinson's freshman numbers at the University of Michigan.

From there, the NFL's average league-wide interception rate has trended inexorably downward, all the way down to a measly 2.4 percent this season. Meanwhile, average completion rate has climbed ever upward; today's 62-percent rate nearly doubles 1933's figure.

Average passing-touchdown percentage rate has held remarkably steady, though, hovering around four percent since 1971.

In the early 1980s, the NFL's average touchdown and interception rates hit parity at just over four percent. Then, the gap between interceptions and touchdowns flipped.

From 2008 to 2013, average touchdown rate has climbed from 4.0 percent to 4.3 percent, and average interception rate has dropped from 2.8 percent to 2.4 percent.

Any football fan old enough to read knows a 2-1 touchdown-to-interception ratio used to be the gold standard for making plays while minimizing mistakes.

So far this season, all NFL quarterbacks have been averaging 1.72 touchdowns for every interception (155 touchdowns to 90 interceptions, per Pro-Football-Reference). 

Oh, did I mention they moved the kickoff back up to the 35 before the 2012 season? In theory, it should have had the opposite effect of the 1994 change—so perhaps scoring would really be exploding right now.

Let's look at the massive increase of shotgun use from 2003 to 2012, with the help of the Premium Football Outsiders DVOA Database (subscription required):

As I wrote back in July:

In 2003, the New York Jets, Oakland Raiders and Tampa Bay Buccaneers took zero snaps from shotgun, and five other teams used it less than 5 percent of the time.

That's unthinkable in today's NFL, where the Houston Texans' 21.6 percent shotgun rate was the lowest in the league. Almost every other team is approaching or above 40 percent, and the Detroit Lions used shotgun 71.3 percent of the time.

Stafford and the Lions are at the forefront of the shotgun revolution. They use shotgun more often than anyone else, throw more often than anyone else (led the NFL in attempts in 2011 and 2012) and have built their entire team around the pass.

They have the best receiver in the NFL, their top three tight ends all catch passes first and block as an afterthought, and their top two running backs are arguably more dangerous catching the ball than running with it.

So, the Lions are dominating the NFL, right?

Well...no.

The Implications

Daryle Lamonica was a five-time Pro Bowler, two-time first-team All-Pro, led the NFL in almost every major passing category in 1969, had a 66-16-6 record as a starter and won three AFL championships. Despite accomplishing all of this in a 12-year career, he is not in the Pro Football Hall of Fame.

Matthew Stafford hasn't done any of that. No Pro Bowls, no All-Pro nods, hasn't ever led the NFL in anything besides completions and attempts, is 19-29 as a starter and lost his only playoff game, 45-28.

Yet, if you look at their total passing numbers, you'd say Stafford had the better career.

The late 1960s through the mid-1970s is sometimes called the NFL's dead-ball era, a chapter of football history like baseball's sleepy offensive period that lasted from about 1900 to Babe Ruth's 1919 breakout season.

If that's the case, the NFL is surely in its steroid era today, where numbers are so wildly inflated across the board that any sense of historical perspective, benchmarks and records is lost.

A few pioneering analysts are trying to reconcile this already, like FootballPerspective.com with its brilliant true receiving yards statistic. Even so, the game has changed so dramatically that era-to-era comparisons are going to be all but impossible.

When the NFL finally pulls the trigger on the 18-game season, it'll really be impossible.

What to do?

The NFL could consider rule changes that tip the playing field back in the defense's favor, but that runs contrary to every decision the NFL's made over the years. Even if it worked, it'd still permanently skew the numbers of only this generation of quarterbacks and receivers.

Instead, the NFL will correct itself. The key to Chip Kelly's revolutionary offense is that it's a high-tempo rushing offense. It's the next phase of the cyclical trend, the next mouse in the game of cat-and-mouse that coordinators play with each other.

Three games into the 2013 season, the Eagles are fifth in rushing attempts, first in rushing yardage, tied for third in rushing touchdowns and way out in front of the rest of the league in rushing yards per attempt.

As the rest of the NFL coaches learn from Kelly the way they learned from Coryell and Walsh, the pendulum could very well swing back toward rushing the ball.

Then again, the Eagles are already ranked eighth in points, with practically identical personnel to the unit that finished 29th in scoring last year.

So, even if the passing explosion is almost over, the offensive explosion is only getting bigger.

All data, information, charts and infographics sourced from Pro-Football-Reference, except where otherwise noted.