Recent NFL rule change has moved the point after a touch (PAT) down from the 2 yard line back to the 15 yard line. So far the chances of making the extra point is down to 95%. That may seem high, but it is actually 4.5% lower!
Over the last five years the PAT completion rate has remained mostly unchanged. The timing of the rule change coincides with a decrease chance of completing the PAT. This is not due to a reduction in the skill of our NFL kickers. Actually, we can see that NFL kickers have been consistently improving in their ability to complete field goals. Overall, NFL kickers are 3.3% more likely to make a field goal in 2015 than they have been in previous five seasons. Kickers are consistently increasing their ability to complete field goals each year.
The chart above shows the probability of an NFL kicker completing a field goal. The chart below shows the same chart zoomed to the scale of the data:
We could argue that their increase in performance is due to improved coaching. The kickers are not asked to attempt kicks which the coach is not confident that they can complete. To test this look at completions by yardage by year:
The table above shows the probability that an NFL kicker will complete a field goal by year and by 20-yard bracket. It looks like these kickers are still doing as well across the various yard-based buckets. So if we compare the field goal completion rate to the PAT completion rate, what do we notice?
Here is the same chart zoomed to the scale of the data. I also added a highlighted point that indicates what the expected completion rate should be for PATs.
The extra point was gone from being a given (99.56%) to having a 19/20 chance. Perhaps this is why the NFL felt motivated to change the rule. Is it a large enough change? If you do the math, it turns out that kickers are now 10x more likely to miss the extra point! Wow- time to adjust our strategies. Will more teams start trying to convert on a touch down?