After the NFL owners approved the new rule moving kickoffs up by five yards, I wrote a post about how the change might affect the number of kickoff returns. Only 16 percent of all kickoffs ended up as touchbacks last year, and I projected that they would more than double. However, my projection was only moderately scientific -- I didn't have all the data for every kickoff. Instead, I was just modeling from the averages of each kicker.
So I thought I'd go back and comb through the actual play-by-play data and see if I could come up with a more definite answer.
First, let's look at how often kickoffs become touchbacks by distance. Mostly it matters where the ball lands. Obviously, if the kick never makes it to the end zone, the returner has to pick it up and take it out. But when it lands in the endzone...
Turns out that the first yard or two don't make a big difference. More than nine in every ten kickoffs landing less than two yards deep in the end zone get returned. But the ratio goes up sharply from there. By the time we get three yards deeper, the returner is only bringing out less than one in three kicks. And once the ball gets seven, eight, or nine yards in, only desperation would cause a player to attempt a return.
The graph shows how much of a difference five extra yards is going to make. Many more footballs last year fell in the 5 to -5 yard range than in the deep zone. As those push forward they get exponentially more difficult to return.
Therefore, when I added five yards to each kickoff from last year and assumed the same return percentage by distance, there was a huge jump in touchbacks. Unless the kickers in 2011 take a big step back, touchbacks should go from 16 percent to just under 40 percent. I know that was my rough estimate last time, but now I can fully back up such a prediction. Also, as I wrote before, this is actually still a low projection. It assumes that kickoff coverage teams won't get any better even though they have five less yards to cover.
Finally, there's the question of how much this changes the role of the players. For starters, kickers with the most powerful legs aren't huge difference makers any more, which should please middle-of-the-road David Akers.
There's an additional benefit for Eagles fans though. Andy Reid hasn't been keen on investing in a kickoff returner. Last year's main man was Jorrick Calvin, who was only slightly better than awful. Plus, kickoff coverage has often been one of the Eagles weakest units. But the rule change takes a lot of the power out of the returner's hands. Their ability to make big plays has dropped by at least at least 30 percent.
Again, this might seem like a small rule change. But it's going to have a big impact throughout the NFL.