When I was younger, I had much different tastes in things than I do these days. I combed through my old CD’s today – what those are is a topic for a different article – and rediscovered my well-worn copy of Aaron Carter’s Aaron’s Party (Come Get It). All the memories of preteen desires to school Shaquille O’Neal in a game of one-on-one came flooding back – and yes, I still remember all the lyrics.

Then the album ended, and the pool party magic dissipated. But that sense of nostalgia is still in me so strongly, that yearning for the innocence and fun of yesteryear. We all have that feeling about things from our past, but sometimes it does cloud where we’ve gotten to today. My musical taste has grown in many different ways, and if I were to immerse myself again solely in teenage pop, I’d do a disservice to the reality of my present.

This is where New England Patriots quarterback Football Perspective did a study on quarterback aging curves, and found that the decline of an NFL passer begins around 30 and rapidly accelerates at 33.

Some older quarterbacks find new ways to compensate for a loss of arm strength and velocity. Peyton Manning, for instance, has increased his rigor and precision of timing, ball placement, and footwork due to throwing ducks. Brady appeared to do none of this on tape. Did it show up in the stat sheet?

Brady has essentially been playing at the same level of excellence for 11 of the last 12 years, both in terms of volume and efficiency. Excluding his injury-shortened season in 2008, he has only passed for less than 3,700 yards three times, under 25 touchdowns twice, and has essentially a 2-to-1 touchdown-to-interception ratio for his career. Yet, the last two seasons saw his efficiency slip a sizable amount. His completion percentage dropped from a better than 65% rate from 2007 to 2011 to 63.0% in 2012 and 60.5% in 2013. Now, that’s still good, but that’s not laser-sight Tom Brady good. It appears that Brady is regressing a bit in his old age.

Time Waits For No One

Here at numberFire, you know that we don’t settle for simple box score perusal. We dig right into the nitty-gritty and figure out why the numbers look the way they do, specifically with our signature Net Expected Points (NEP) metric. Net Expected Points looks at specifically what a player did on the field and how much that contributed to his team’s chances of scoring. Basically, you win by getting points, and if a player is helping you get those points more easily, their NEP is higher.

Specifically, what we will look at with Tom Brady is his Passing NEP, which is a measure of the number of points he contributed to the Patriots scoring on any and all passing plays. Excluding his rookie season and the injury-shortened 2008, prior to last year, Tom Brady averaged 115.68 Passing Net Expected Points per season, which actually would have put him fourth in the NFL among passers in 2013.

We can also examine Passing NEP per drop back, a simple efficiency measure of how many points each drop back generates for a quarterback. From 2001-06, Brady averaged a fairly mediocre 0.10 Passing NEP per drop back rate, which isn't incredibly strong. But we knew that - Brady wasn't the same type of quarterback we've come to know prior to 2007. Once the 2007 season hit, Brady went from playing as a mere mortal to a passing machine. His age 31 season in 2007 was a career year, and a numberFire Passing NEP record until Peyton Manning's 2013 season.

From that point forward in his career, Brady has tallied a 0.24 or higher in Passing NEP per drop back, and on average, brought in a 0.32. For reference, that mark would put him tied for third among qualified passers in 2013. This new hyper-efficiency is what we've come to expect from Brady, and yet that may be slipping back to merely average.

In 2013, both Brady’s totals and efficiency marks have all declined after elite level play the past few years. The chart below shows his totals in Passing NEP, as well as his efficiency ratings in Passing NEP per drop back and Passing Success Rate, which measures the percentage of passes that contribute positively towards a player's NEP score. As you can see below, in 2013, he accumulated his second-worst season in Passing NEP over the past decade (68.71 Passing NEP). On a per drop back basis, he ranked 10th in the league among relevant passers, which was his absolute worst mark over the past decade.

All of these numbers show the beginnings of a decline back to good, but not elite quarterback play. After a career year in 2007, he was still playing at a very high level. Although he did have a late career spike in production during his age-34 season, counting on that to happen again is a risky proposition, especially considering the lack of reliable pass-catchers around him these days. While dropping merely to 10th place in efficiency may seem a small qualm, it was not so long ago that Manning and Brady were the top two in the league. We've begun to expect Brady's play to be elite annually, but this dings his value quite a bit.

Looking Forward

It’s clear - for a lot of reasons - that Tom Brady is falling off the pace as an elite NFL passer, so what should the Patriots do next? One positive of Brady’s regression is that it should be more gradual than the average quarterback at his age. New England can expect continual decreases, but not a drastic implosion. Brady may not be at his stellar 2007-12 numbers now, but he's still a good NFL quarterback, and has merely regressed to his pre-2007 levels of play. He will be around to finish his contract and still be a key player in the team’s current winning window.

Head coach Bill Belichick made a savvy move, though, selecting Jimmy Garoppolo from Eastern Illinois in the second round of this year’s draft. Garoppolo could be an acceptable heir to Brady someday in the future if Ryan Mallett leaves town or never fully pans out. The window is closing sometime soon for this iteration of the New England dynasty, but there is a succession plan in place. Both Tom Brady and the Patriots organization should continue to thrive, and they still have a legitimate shot to win with the face of their franchise.