The NFL Scouting Combine is always a big deal for stat lovers. It gives them – us – the ability to put actual numbers to the size, shape and athleticism of a player. The players, in essence, become data points.

A favorite combine drill among NFL fans is the famous 40-yard dash. It’s the drill that introduced the world to fed us the image of a shirtless Andre Smith – one that will haunt us in perpetuity.

The 40 is often debated by polarizing views. Some see it as completely worthless, while others live and die by the number. Admittedly, I’ve always sided with the latter crowd, though I do think some make too big of a deal about it.

Because this is a fantasy football-driven NFL (world, even), a lot of people only care about how something NFL-related impacts their fantasy team. They care about quarterbacks, running backs, wide receivers and tight ends. And when it comes to 40 times, wide receiver is the position in fantasy that’s analyzed most.

Why shouldn’t it be? The job of a wide receiver is to gain separation – to get open. Having speed (among other attributes, of course) is naturally going to help a wide receiver perform better. That’s not something necessarily in question with those who hate the 40-yard dash. What’s in question is the “how much” does it matter?

Does it really make a difference if Wide Receiver A runs a 4.39 40, while Wide Receiver B comes in at 4.61? I mean, I don’t have my masters in mathematics, but at a high level, it doesn’t seem like it should. Especially considering a 40-yard dash measures straight-line speed, and the guys aren’t even wearing pads.

But making subjective conclusions isn’t what we do here at numberFire. I wanted to dig into the metrics and see if there was something to these wide receiver 40 times. So that’s what I did. And here’s what I found.

The Study

We use a metric called Net Expected Points (NEP) here at numberFire when we analyze football. In essence, NEP measures how many real points a player is adding for his team based on down-and-distance and game situations on a football field. For a much more in-depth look at NEP, you can read up in our glossary.

There are two meaningful ways to measure a wide receiver’s production based on NEP. The first is by looking at how many points the pass-catcher adds on all targets. This is what we’ve called Target NEP, and it clearly favors efficient wideouts with good quarterback play and high catch rates.

Another way to measure is through what we call Reception NEP – a look at the number of points added by a receiver on receptions only. This metric is more helpful for fantasy football purposes, as higher-volume receivers will often times see higher Reception NEP totals. After all, if you’re measuring the points added on receptions only, pass-catchers with more targets are naturally going to see more receptions.

Our NEP metric is a production one. It tells you how a player is contributing for his team, and delivers it into a nice, consistent number. Rather than trying to find the importance between yards, touchdowns, yards per catch and yards after the catch, we can look at Net Expected Points – we can look at a single number.

And that’s what I did for this study. I took every 100-plus Reception Net Expected Points season from wide receivers since the year 2004 (10 years worth of data), and associated those scores to that player’s 40 time. If, for instance, a wide receiver appeared on the list more than once (which was common), then that was fine. That wide receiver’s 40 time would be counted more than once as well.

In essence, I wanted to see if there was any sort of relationship between 40 times and having a top-tier NFL receiving season, defined as scoring 100-plus Reception Net Expected Points in a given year. Adding 100 points through receptions is a pretty big deal at the wide receiver position, as only 10 to 15 players do it each season. This study, in turn, is only looking at those elite guys.

There have been 125 instances over the last 10 years where a wide receiver hit the 100-plus Reception NEP mark. It’s a pretty convenient number, as I was able to divide the seasons out into five 25-player tiers: Tier 1 (the best Reception NEP seasons; players ranked 1-25), Tier 2 (26-50), Tier 3 (51-75), Tier 4 (76-100) and Tier 5 (101-125). The results can be found below.

Tier 1

Since 2004, the best wide receiver season we’ve seen in terms of Reception NEP was, not surprisingly, Calvin Johnson’s record-breaking 2012 campaign. That year, Megatron added 162.56 points for the Lions on receptions only, a little less than six points more than what Randy Moss did for the Patriots in 2007.

Megatron ran a 4.35 40-yard dash, while Randy Moss’ was a staggering 4.25.

As you move down the list of top Reception NEP performances through the years, you’ll find Wes Welker’s 2011 season (4.65 40-yard dash time), Josh Gordon’s 2013 campaign (4.43) and even Terrell Owens’ 2007 season (4.45).

Of these top-25 receiver seasons, the only players who didn’t run a sub-4.6 40 were the aforementioned Welker, Larry Fitzgerald and Brandon Lloyd. In other words, 22 of the 25 best wide receiver seasons since the year 2004 have involved players who ran the 40-yard dash faster than 4.6 seconds.

Moreover, Chad Johnson (4.57), Sidney Rice (4.51) and Brandon Marshall (4.52) were the only wideouts within this tier who ran the 40 between 4.5 and 4.6 seconds. That leaves us with 76% of this category seeing sub-4.5 40-yard dashes.

The average 40 time of this group clocked in at 4.447, while the median speed was 4.45. And while you may think that players like Andre Johnson and Calvin Johnson are skewing this with their multiple high-end performances, keep in mind that this group actually involves 22 different wide receivers.

Tier 2

The next tier starts with Braylon Edwards’ 2007 season, one where he accumulated a 122.90 Reception NEP score. Chad Johnson’s 2009 campaign was one slot ahead of him (and, in turn, within Tier 1), but Ochocinco was only .07 Reception Net Expected Points better than Edwards. Considering Chad Johnson ran the 40 at 4.57 versus Edwards’ 4.45, the Tier 1 group could have been even better had Edwards, I don’t know, caught an additional pass in 2007.

But, alas, Edwards made his way into Tier 2. With him is Roddy White’s 2010 season (4.47 40-yard dash), Anquan Boldin’s 2013 (4.72) and Lee Evans’ 2006 (4.39), among others.

In the end, the average 40 time from the 26th- to 50th-ranked wide receiver seasons since 2004 was 4.488, .04 seconds slower than Tier 1 players. The median 40 time was 4.46, also slower than the Tier 1 guys. Moreover, there were eight instances of a 40 time being higher than 4.5 seconds, two more than the top seasons at the position over the last 10 years.

Tier 3

Thus far, we’ve seen a gradual decline in 40 times when looking at the best wide receiver seasons since 2004 in “tiers”. Did it continue into Tier 3? Kind of.

Tier 3 saw some familiar faces, as Randy Moss’ 2009 campaign, Larry Fitzgerald’s 2007 season, and Chad Johnson’s 2004 one all were listed within it. On average, this tier saw a 40 time of 4.478 seconds, slightly faster than Tier 2. However, because some 40 times (like Randy Moss’) can skew that a bit, the median may be a better indicator of how these players ran. And that median was even slower than Tier 2, sitting at 4.48 seconds.

In addition, nine of the players ranked 51st to 75th ran the 40-yard dash in 4.50 seconds or worse. That’s one more instance when compared to Tier 2, and three more than Tier 1.

Is it surprising that we’re getting slower and slower as we move down this list? Not to those who love 40-yard dash times.

Tiers 4 & 5

I won’t bore you with the specific players anymore, but I will tell you that wide receiver seasons ranked 76th to 100th saw a dip in 40 times once again. The average 40 within this tier was 4.482 seconds, while the median time was 4.48 as well. These numbers match up with Tier 2 and Tier 3, sure, but consider this: 10 players ran the 40 slower than 4.50 seconds in this group, a number higher than the previous three tiers.

Guess what? Tier 5 continued to get slower. In this final tier – pretty good seasons, but not the best we've seen – the average 40 time among receivers was 4.500, with the median time sitting not as pretty at 4.51 seconds.

Moreoever, the only instance where a player in Tier 5 ran a 4.40 dash or better was Torrey Holt’s 2006 season (Holt ran it in 4.38 seconds). Compare that to Tier 1, where nine of the 25 players ran the 40 within that range.

Bringing It Together

This isn’t the most scientific study in the world, no, but it’s certainly something that’s alarming. If you didn’t follow some of the numbers above, I’ve placed them in a clean table for you below:

As you move down each tier, players clearly get slower. And while this is only looking at top-level performances in the NFL over the past 10 seasons, it's still alarming to see a clear relationship in 40 times and actual production in the NFL.

This isn't to say that a 40-yard dash time is all you need to measure with a wide receiver - plenty of other factors weigh in to whether or not a pass-catcher will be successful. However, any time we can get a data point that increases our probability in finding a gem, why would we ignore it?

That's why 40-yard dash haters typically pick and choose examples as to why the drill is worthless. Yes, Larry Fitzgerald and Anquan Boldin are insanely effective wide receivers at the pro level, and both ran pretty mediocre 40-yard dashes. But for every Anquan Boldin, there are plenty of examples as to why 40 times matter. Hopefully this shows you why.

Again, the goal here isn't to prove that 40 times mean everything when it comes to a wide receiver's achievements in the NFL. But ignoring it - as an analyst or even a fantasy football owner - probably isn't the smartest idea. Speed is important, and if you want high-end efficiency, you're going to need it.