Skip to main content
Menu
Dick Vermeil Retired A Decade Ago. Will You Please Stop Using His Damn 2-Point Conversion Chart?

Before the Super Bowl in February, we published a fairly comprehensive guide for when to go for 2, simplified into one slightly complicated (but very easy to use once you get the hang of it!) chart. In addition to hopefully demystifying how to judge a lot of borderline situations, we identified some fairly clear-cut cases in which NFL coaches should choose to go for 2 but don’t. Ever.

My hope, of course, was that teams would read this (or figure it out on their own) and that we’d see an immediate and cataclysmic shift in 2-point strategy — like going for it when down 4, 8, or 11 after scoring a touchdown late (which are not only real cases, but ones that are usually clear-cut and significant). But, alas, no such luck.

The logic is pretty simple: If you can estimate your team’s chances of winning with an X point lead/deficit (X points being how many points you are up or down following a touchdown) and your chances of winning with X+1 and X+2, the decision follows from simple arithmetic. In fact, given that 2-point attempts and extra-point attempts taken from the 15-yard line (under the new rules implemented in 2015) now have roughly the same expected point value (both around 0.95 points), the choice is easier than ever. Simply calculate (or estimate):

  • The improvement in win percentage if your point margin changed from X to X+1.
  • The improvement in win percentage if your point margin changed from X+1 to X+2.

If the first number is greater, kick the extra point. If the second is, go for 2.

Now, you can estimate or intuit these differences on your own on the fly, or you can use a fancy win probability model like we have,1 but the logic is the same.

Of course, we’ve taken it a bit further — our chart uses multiple sets of assumptions to create a range for each scenario covering teams that are relatively better or worse at 2-point conversions than our baseline. In case you missed it, here’s the chart:2

A quick note on reading this chart: It may look a little “loud,” but that’s a feature for looking up scenarios lightning-fast. For a quick approximation, you first look at the minichart corresponding to the point spread (after the touchdown). If the quarter you’re in is shaded bright purple, you probably want to kick; if it’s bright orange, you should probably go for it. If you’re in a rush, you could stop there and be in pretty decent shape.

Through the first two weeks of this NFL season, teams have gone for 2 (from the 2-yard line) eight times overall. More importantly, of the 30 times that the numbers say they should have gone for 2, they did so just four times, for a rate of 13 percent. Since 2015, in the regular season and playoffs, teams that should have gone for 2 have done so around 15 percent of the time.

Now, of course it’s possible that some teams are better or worse at going for 2 than average, but it isn’t possible that 85 percent of teams are worse than average. I’ve also calculated how often teams should “clearly” go for 2 — meaning situations in which they should go for it even if they are relatively quite bad at 2-point attempts3 — and there have been 16 such cases through Week 2:4

Times when teams clearly should have gone for 2

2017 NFL season through Week 2

WEEK TEAM OPPONENT QUARTER TIME SCORE AFTER TD MAGNITUDE WENT FOR IT
1 Cleveland Pittsburgh 4 3:36 -5 2.23
1 L.A. Chargers Denver 4 7:00 -4 1.62
1 Chicago Atlanta 4 7:26 -4 1.33
1 Detroit Arizona 3 3:07 -2 1.28
2 Arizona Indianapolis 4 7:38 -4 1.28
1 N.Y. Jets Buffalo 3 2:00 -2 1.24
1 Detroit Arizona 4 9:27 4 0.43
1 L.A. Chargers Denver 4 8:10 -11 0.43
1 Jacksonville Houston 2 0:49 18 0.29
1 Baltimore Cincinnati 2 1:28 16 0.29
1 Houston Jacksonville 3 9:09 -13 0.24
2 Cleveland Baltimore 2 4:56 -8 0.24
2 New Orleans New England 4 5:04 -17 0.10
2 Tennessee Jacksonville 3 2:49 19 0.05
2 Dallas Denver 4 14:24 -19 0.05
2 Philadelphia Kansas City 4 0:08 -8 0.05

Magnitude is the amount that a team’s expected win percentage is improved by making the right decision.

Source: ESPN Stats & Information Group.

Teams made the correct decision in four of those 16 cases, for a 25 percent rate. (For comparison: Since 2015, regular season and playoffs combined, teams have gone for 2 points 27 percent of the time in “clear go” scenarios.)

Of course, a decision being clear-cut doesn’t mean that it matters a whole lot, but note that even among the decisions with the most significant consequences, teams are still making the wrong choices regularly (most likely because of adherence to Dick Vermeil’s rigid and outdated system that leads them to repeat the same mistakes over and over). In particular, the aforementioned scenarios of being down 4, 8, or 11 points late are both quite clear and quite important.

Another significant case is when a team scores to pull within 2: Go for 2! This may seem like an obvious one, but since 2015, teams in this situation have chosen to kick the extra point as late as the fourth quarter (once, which is way too many times), and they’ve done so half the time in the third quarter (6 of 12, and still very bad) and 77 percent of the time in the second quarter (10 of 13, and still pretty bad, especially for such an early decision).

This season, teams down 4, 8 or 11 late are holding steady at a 0 percent correct rate, having attempted extra points five out of five times when they “clearly” should have gone for it. That means that over the past three season, they’ve gotten these right exactly zero times in 105 chances.

On a slightly brighter note, teams have been down 2 points after a touchdown twice this season — both in the third quarter — and they’ve correctly tried to tie the game both times! It’s not quite the revolution — it isn’t really even shots fired. But maybe, just maybe …

Footnotes

  1. Specifically, a version of the model built by Brian Burke of ESPN’s Stats & Information Group.

  2. You should be able to use this chart to pretty accurately assess most decisions you see. If you’re skeptical of the chart, you could intuit your own using the method outlined in that article.

  3. I set this threshold at a 40 percent expected conversion rate (the same as the bottom of the range lines in the chart above). Or 7.5 percentage points lower than the baseline conversion rate assumption of 47.5 percent. This is a rough best estimate (after discussion with Burke, among others) for how bad teams who are very bad at 2-point conversions actually are).

  4. For this season’s scenarios, I’ve analyzed each attempt individually (down to the second), while the chart above is calculated minute by minute, so there may be slight variations between the two.

Benjamin Morris researches and writes about sports and other topics for FiveThirtyEight.

Filed under

Comments