My 2022 NFL Playoff Preview!

Check out the code on my Github!

What is Net Yards Per Pass Attempt?

One of the most predictive metrics for NFL team success is one that may not appear on many broadcasts or come up in casual conversations. It may not be as obvious as turnovers or as flashy as a great pass rush, but it can be quite powerful in separating a good team from a bad one. Net yards per pass attempt is simply found by taking a team's offensive yards per pass attempt and subtracting the defenses's yards per pass attempt allowed. For example, we can see from the table on the right that for the season, Tom Brady's Buccaneers offense averaged 6.3 yards per pass attempt, while the Bucs defense allowed just 6.1 yards per pass attempt to opposing quarterbacks. This comes out to a net yards per pass of 0.2 which means that, on average, the Bucs gained 0.2 more yards than their opponent on each pass play. This may seem insignificant, but think about how many pass plays there are in a season, and you can quickly see how those yards can add up.

The beautiful thing about using net yards per pass as a metric is that it gives a numerical value to the intuitive concepts that any football fan can see impact success. More specifically, it captures how much more effectively a team's offense is throwing the ball compared to their opponents. You may not think of it like that while watching the game on Sundays, but every fan knows their team in a good spot if they can pass the ball more efficiently than their opponent.

Figure 1
2022 table
Net Yards per Pass Attempt and Winning Percentage for 2022-23 Playoff Teams
Figure 2
Historical Plot
Historical Analysis

As previously stated, net yards per pass attempt is one of the best predictors of winning percentage historically. I gathered offensive and defensive passing statistics for every NFL team from 1971 to 2019 as well as collected the team's record for that respective season. As a result I was able to perform a Linear Regression using net yards per pass as the explanatory variable and win percentage as the response variable. The results are shown by the red line on the plot to the left. As you can see, the trend line fits the data well.

Now for some statistical jargon: the correlation coefficient (R) of this regression was .718, while the coefficient of determination (R-squared) was .516. What this value of R means in simpler terms is that there is a strong, positive, linear relationship between net yards per pass and winning percentage. The data exhibits a linear upward trend meaning the better the team's net yards per pass, the better their win percentage is expected to be. Once again, the plot on the right offers clear evidence of this being the case. An R-squared value of .516 tells us that 51.6% of the variation in winning percentage can be explained by a team's net yards per pass. There are certainly models that can explain more than 51.6% of the variation, but for one simple metric, this is quite good.

What it Means for the 2022-23 Playoffs

Unfortunately for those that are looking for a flashy prediction, you won't find one here. Of the 51 Super Bowl champions from 1971-2021, 35 of them had a net yards per pass attempt of 1.0 or over. So slightly over 2/3 of all super bowl champions since nfl.com began tracking stats have hit that benchmark. Additionally, the last 3 Super Bowl champions (Chiefs, Bucs, and Rams) have all exceeded 1.0 net yards per pass atempt. By looking at Figure 3 on the right, we can see that there are 5 teams that have reached or exceeded 1.0 net yards per pass this year. The 4 Super Bowl favorites, Chiefs, Bills, Eagles, and 49ers, and then the Dolphins, would seem to be the prime candidates to win the Super Bowl this year. With Miami being forced to play 3rd string QB, Skylar Thompson, I think it's fair to cross the Dolphins off from this group as their passing attack is a shell of itself at the moment. Once again, I'm not going out on a limb here by predicting one of the top 2 seeds from either conference will win the Super Bowl this year, but based on historical trends, that is likely to be the case.

Perhaps more interesting are the pair of first round underdogs that would seem to have the advantage by net yards per pass. Both the Jaguars and Giants are underdogs against the Chargers and Vikings respectively, despite having the advantage in net yards per pass. In fact, the Vikings even have a negative net yards per pass, joining the Ravens as the only teams with a negative margin to make the playoffs this year. Both those teams are looking to be just the 3rd team in over 50 years to win the Super Bowl with a negative net yards per pass, joining the 2007 Giants and 2014 Patriots. Much has been made of the Vikings fluky record considering their point differential, and that is given further credence by Figure 3. I'd look for the Giants to pull off one of the few "upsets" of this years playoffs against the Vikings. It may not be a playoffs full of surprises, but it's sure to be entertaining as usual.

Figure 3
2022 table