College Football: The statistical impact of the 2018 kickoff rule

It’s been two years since the new 2018 college football kickoff rule. How have teams reacted? We will look at the stats and see.

Before the start of the 2018 season, the NCAA implemented a new kickoff rule that states that a kickoff returner may signal for a fair catch anywhere within the 25-yard line for a touchback that results in the drive starting at the 25.

The rules committee suggested this rule tweak with the goal of increasing the number of touchbacks, which in turn would hopefully decrease the number of injuries that occur during kick returns.

Now that two seasons have passed with the new rule in place, how have teams adjusted their kickoff game plans? With coaches around the country being so centered around efficiency (and hopefully player safety), have they taken the free extra five yards for a guaranteed start at the 25 yard-line and little risk of injuries? Or is the prospect of a big momentum-changing return too attractive to pass up?

Let’s take a look at the numbers and see.

Before getting started, a word on the methodology of the data. All data was obtained from cfbstats.com and covers from the 2013 to the 2019 seasons. This provides five years of data prior to the rule change and two years of data after.

The data covers only FBS teams, but due to teams each season either moving up to FBS or down to FCS, a consistent 123 team sample was maintained by removing the following teams: Idaho, Appalachian State, Georgia Southern, Old Dominion, Charlotte, UAB, Coastal Carolina, and Liberty. Sorry, folks (except you, Liberty).

Kick Returns

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In general, the number of kick returns have steadily declined for a while now due in large part to the increased emphasis on player safety, but also due to coaches wanting to take the free guaranteed yardage to start out a drive. This is apparent in the graph above, but it is also easy to see that the largest drop off in average returns per game was after the rule change.

Before the rule change, teams averaged 3.11 returns per game. After, that average has dropped to 2.60 returns per game. This may not seem like a large drop, but there is already a limited number of kickoffs in each game so a decrease of over a half of a return is still telling.

As you would expect, this also led to a dramatic decrease in the average return yardage gained per game since there is just less returns happening. Average return yardage has dropped from 65.88 yards per game to 48.19 yards per game after the change.

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Interestingly, the total number of kick return touchdowns plummeted from 2017 to 2018 following the rule change, but saw a major increase again back to almost pre-2018 normals in 2019. This is most likely due to just how volatile kick returns are.

Across all data used for this article, the chance of getting a touchdown on a kick return is right around 1.17 percent. Not great odds, but kick return touchdowns are huge momentum-changers that can electrify a team as well as the entire stadium. The two graphs below show the total number of kickoff return touchdowns and the percentage of returns that get taken to the house. It looks like 2018 was just a down year and 2019 was a great year for taking kickoffs all the way.

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Overall, returns have clearly been on the downswing, with the most significant change following the introduction of the new rule. What the rule really did, however, was make it much more appealing to take the touchback for the free extra yards. Did teams take the bait?

Touchbacks

Touchbacks are the safety net that coaches love for kickoffs. As explained above, the chance of taking a return back for a touchdown is slim. This doesn’t take into account returns that gets the team beyond the 25-yard line and is therefore a successful return, but the extreme of a touchdown is fun to look at nonetheless so get off my back.

It’s also important to keep in mind all of the critical failures that can arise from deciding to run out a kickoff. Injuries are the worst ones, but there are also potential fumbles and penalties that can set a team back.

With modern coaches preaching efficiency day and night, starting the drive at the 25 is the safest way to go.

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The above graph shows the steady increase in touchback percentage throughout the years, rising from a little over a third to just under a half of all kickoffs ending with a touchback. This is of course the opposite trend of the first graph showing average kick returns, which makes sense because if someone is not returning than they’re kneeling.

However, there isn’t as much of an increase as one would expect following the rule change, and then in 2019 the percentage even slightly decreased (granted it was less than a one percent change).

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Fancy percentages are nice but raw numbers tell the story better, so that’s how we’ll wrap things up. The rule change before the 2018 season led to the largest increase in total season touchbacks in the data shown, up almost 300.

Again, the random decrease shown in 2019 is confounding especially because it’s the only decrease in total touchbacks per season we’ve seen since 2013 given the steady yearly upswing in kneeling on kickoffs. Are coaches correcting course after overreacting in 2018 following the rule change? Are the current batch of athletes more apt to just try ripping off a huge return? Or is it all random and is looking at numbers a waste of time?

Clearly less and less kickoffs are happening, which is safer for the players, and either way the rule change certainly did not hurt this trend.

It will be interesting to see how the data looks after a few more seasons of the new rules. There has also been the concept of removing the kickoff entirely that has long been tossed around.

Hopefully we get a season at all this year. See you next time to look at more numbers and make cold takes about what they mean.

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