Hidden Stat Line: Advanced Stats & Applications for 2020

It wasn't so long ago that yards per target may have seemed like an "advanced" statistic. Nowadays, we can use the abbreviation without spelling it out first, as YPT has made its way into the lexicon of the typical fantasy football player. It's become the quick, oft-cited stat for measuring receiver efficiency, though it arguably tells as much about usage as it tells us about the quality of a player (more on that later).

Nowadays, we have other stats that have become increasingly popular with writers and analysts, if not with the majority of fantasy football players overall. Below we have a quick introduction to some of the newer metrics that have become popular among competitive fantasy players. A few of the stats discussed below can be found on our Advanced Stats page.

Air Yards (AY)

Used for both pass catchers and quarterbacks, "air yards" measure a player's distance downfield relative to the line of scrimmage at the moment when a pass is caught, intercepted or falls incomplete. For example, this catch by Terry McLaurin features 14 air yards and 61 yards after the catch, resulting in a 75-yard touchdown:

Now, here's a drop, which equates to 20 air yards for both McLaurin and Case Keenum, but zero passing or receiving yards:

The QB leader for 2019 air yards was Jameis Winston, whose 6,486 put him nearly 1,000 ahead of second-place Dak Prescott (5,539). The leader among pass catchers was Julio Jones (1,911), though Mike Evans (1,778) probably would've taken the cake if he hadn't missed three weeks at the end of the year.

You might be wondering why any of this matters ... after all, we don't need advanced stats to figure out that Winston threw a lot of deep passes and Evans got a lot of deep targets. However, you may not have realized that Odell Beckham was No. 5 in air yards (1,720) and Curtis Samuel was tied for 11th (1,520). Both players were disappointments, but it wasn't because their coaches/quarterbacks didn't try to get them the ball downfield. This is probably useful to know, though it arguably would be more useful if the Browns and Panthers hadn't brought in new coaches.

Personally, I've found AY to be a useful statistic for daily fantasy tournaments, helping me identify wide receivers and tight ends with low price tags and hidden potential for a big game. Take, for example, the imaginary case of Mr. Smith, who catches seven of 15 targets for 100 yards through the first three weeks of the season. That's not exactly a profile that stands out at first glance, but what if he's 12th in the league with 300 air yards? Now we're talking about a guy with hidden potential for a big game around the corner, as he isn't getting a ton of targets but is at least getting shots downfield — rather than short passes — when the quarterback looks in his direction. 

AY can also be useful for identifying upcoming breakout or rebound seasons for a wide receiver. Two players in 2018 had more than 1,500 air yards and fewer than 1,000 receiving yards: John Brown and Jarvis Landry. Both went on to have much better years in 2019, topping 1,000 yards and scoring six TDs apiece.

That said, I mostly find AY useful as an input for other statistics ...

Average Depth of Target (aDOT)

ADOT might just be the new YPT, becoming a regular staple of fantasy football conversation. For pass catchers, it's calculated as AY/targets. For quarterbacks, it's AY/pass attempts. The result? A handy statistic that gives us a quick picture of how teams use players.

The 2019 QB leaders for aDOT were Matthew Stafford (11.3), Winston (10.7) and Ryan Tannehill (10.1), reflecting an aggressive approach to the passing game with intermediate and deep throws on a regular basis. On the other end of the spectrum we see Derek Carr (6.6), Jimmy Garoppolo (6.7) and Drew Brees (6.9), each of whom completed more than 69 percent of his pass attempts.

Shorter passes are easier to complete, so overall we'll see a negative correlation between aDOT and completion percentage. For that reason, we should really take notice when someone like Stafford leads the league in aDOT and also ranks a respectable 16th (of 32 qualified passers) with a 64.3 completion percentage — that's good stuff, albeit in a half season thanks to a Week 9 season-ending injury.

On the other hand, we might be critical of someone like Tom Brady or Gardner Minshew. The future Hall of Famer finished 24th in aDOT (8.1) and 27th in completion percentage (60.8), while the rookie was 25th (7.9) and 29th (20.6), respectively. It makes sense for Winston to rank near the bottom of the league in completion percentage while repeatedly chucking the ball deep, but QBs who are relying on shorter passes should probably be closer to a 65 percent completion rate.

In 2019, there were eight quarterbacks who finished in the top half of the league for both aDOT and completion percentage: Tannehill, Stafford, Deshaun Watson, Russell Wilson, Lamar Jackson, Philip Rivers, Patrick Mahomes, Dak Prescott. That's not to say they weren't also getting help after the catch, but the combination of a strong aDOT and strong completion percentage is a good indicator of a QB who is pulling his own weight and then some.

ADOT for pass catchers is arguably even more important, with multiple studies showing it's among the quickest stats to stabilize and also one of the "stickiest" from year to year. There were more than a few analysts who viewed A.J. Brown as a possession receiver coming out of Ole Miss, but we saw strong evidence of the Titans believing otherwise when his aDOT was 11.9 (on 45 targets) through the first 10 weeks last year. The usage hinted at hidden upside, which came to fruition in the biggest way possible over the final six games of the regular season.

Yards Per Route Run

Here's a basic question — what's the sample by which we should judge a pass catcher?

A) His targets.

B) All pass plays where he's on the field.

If we use A as the measure of efficiency, we probably end up overrating lower-volume receivers and punishing higher-volume ones. Davante Adams is asked to make catches even when he's tightly covered, while someone who plays in the same offense as Michael Thomas and Alvin Kamara will mostly only see targets when he's open. Heck, Jared Cook put up 10.8 YPT last year, while Zach Ertz was down at 6.8.

The problem with using B is that a player can't force his QB and coach to throw him the ball. Sometimes, a receiver who does well with his targets really does deserve to see more passes, rather than simply being a beneficiary of circumstances.

Ideally, we'd judge a pass catcher by both factors (among other things), which is where yards per route run (YPRR) comes in handy. The stat is exactly what it sounds like, counting all of a player's receiving yards and then dividing them by the number of routes he ran. Pro Football Focus pioneered the statistic, and Julio Jones is known as the champion of it, regularly landing around 3.0 YPRR.

And unlike YPT, YPRR is pretty sticky from year to year, offering predictive value that's otherwise rarely seen with efficiency stats for pass catchers. When I'm looking for the next big breakout at wide receiver, I usually start by looking at guys who put up big numbers for YPRR in the previous season but didn't have the opportunity to run a ton of routes. 

Prime examples for 2020 include Marquise Brown and Will Fuller. Generally speaking, volume stats are far more stable than efficiency ones, but it doesn't take a genius to figure out why Brown and Fuller may see a lot more volume this year.

Targets per Route Run (TPRR)

While I was working on this article, I stumbled across a twitter thread posted by CBS Sports' Ben Gretch, which reminded me of an old Chase Stuart article I've read a few times over the year. The gist of it is that targets per route run (TPRR) is actually stickier than YPRR. Anyway, I'll just post Ben's twitter thread, because he explained it better than I would:

What Ben is saying makes a lot of sense intuitively, because YPRR is just YPT combined with TPRR. Volume stats tend to be more stable than efficiency stats year over year, so it makes sense that you'd get a stickier metric by only looking at the volume component. Unfortunately, TPRR hasn't really caught on as a popular stat, so you won't find it published on fantasy sites.

In terms of potential 2020 breakouts, this makes me fell a bit more hesitant on Mecole Hardman, whose 13.1 YPT obscured the fact that he was targeted on a very low percentage of his routes (12.3 percent, per PFF). Part of that involves sharing the field with Tyreek Hill and Travis Kelce, so it's probably not a knock on Hardman as much as it's a commentary on his situation.

On the other hand, Preston Williams produced only 7.1 YPT, but he was targeted on 22.1 percent of his routes (per PFF). History suggests the basis for Williams' production is more sustainable than the basis for Hardman's significantly sexier production.

Other 2020 breakout candidates who were above .2 TPRR last year include Will Fuller (0.21), Marquise Brown (0.20), Hunter Renfrow (0.23), Diontae Johnson (0.20) and Steven Sims (0.24). Of course, context is still important, so we can't ignore things like sample size or future role projections. And it's often the case that slot specialists are targeted on a high percentage of routes, but they aren't running as many routes because they come off the field when their team uses only one or two receivers. Plus, they tend to see shallower targets, making it hard to sustain big YPT averages over larger samples.

Now for some 2020 breakouts candidates who were targeted on a low percentage of their routes last year: Darius Slayton (17.0), Allen Lazard (17.3), Breshad Perriman (14.5 percent, obvious caveat), Anthony Miller (17.3) and Curtis Samuel (15.9). 

Passing TD Rate

Simply defined as the number of passing touchdowns divided by the total number of pass attempts, TD rate is a stat that wasn't really at the center of my radar before this offseason. Anyone with even a rudimentary understanding of analytics knows touchdowns are less predictable/reliable than yards, so we can generally expect some regression toward league-average whenever a player winds up as a drastic outlier (in either direction) for TDs/yards.

But that's not to say TD rate is simply luck. Aaron Rodgers' career number is 6.0 percent, while Joe Flacco is at 3.7 and Kyle Boller at 3.2. League average in 2019 was 4.5 percent, compared to 4.8 in 2018 and 4.2 in 2017.

Better quarterbacks will tend to post better numbers, but the year-to-year correlation is quite low, with 4for4's TJ Hernandez finding it was just 0.23 for a sample of the last 11 years. Compare that to passing yards per game (r=0.66) or completion percentage (0.61) and you can see why fantasy drafters should be skeptical of QBs who post top-notching QB rates without the backing of strong numbers in the "stickier" categories.

Of course, last year's TD rate outliers — Lamar Jackson and Ryan Tannehill — also excelled in a number of other stats. Daniel Jones is one guy who stands out for having a high TD rate (5.2, 11th) while most of his other numbers were ordinary or subpar. Meanwhile, Derek Carr was second in completion percentage (70.4) and 10th in YPA (7.9) but only 22nd in TD rate (4.1). 

And Jared Goff didn't exactly have his best season, but his 3.5 TD rate (28th) should at least regress back toward league average, if not to his 2017-18 level (5.9, 5.7). The Rams' problems on offense last year were real, but they weren't so drastic that we'd expect a QB with 4,638 yards and 16 INTs to throw for only 22 TDs. It was strange for a team that relied on its passing game so much to have nearly as many rushing TDs (20) as passing scores (22).