When are teams being more aggressive on fourth down?
More than ever, NFL offenses are staying on the field on fourth down. In the 2019 season, the rates with which teams have gone for it on both fourth-and-1 and fourth-and-2 plays are higher than in any season during the last two decades.
To answer the question of when teams are going for it — even after knowing the distance needed for a first down — we need additional information. Where on the field is the team? What is the score? How much time is left?
Using statistical modeling, we estimated the likelihood that a team would go for it on fourth down — given distance, score, yard line, and time remaining — for each of the last 15 regular seasons. Here’s a plot that compares the likelihood that a team will go for it in 2019, relative to the average from the 2005—2018 seasons, shown across the length of the field (left to right). The plot assumes that the game is tied at the start of the second quarter, when the increase in fourth-down aggressiveness has picked up the most. Each line corresponds to a different distance category.
The uptick in fourth-and-1 aggressiveness has primarily happened in two scenarios — when an offense is around midfield and once an offense has fewer than 10 yards to go for a touchdown. Increases in all other go-for-it rates are primarily centered around the opponent’s 40-yard line. As an example, teams at the opposing 40-yard line when facing a fourth-and-2 are going for it 25.1% more often in 2019 relative to past seasons.
As additional anecdotes, in 2019 here are the seven fourth-down attempts where a team would’ve gone for it less than five percent of the time.
- Baltimore successfully went for it on fourth-and-3 at the Kansas City 9-yard line during Week 3. The game was tied with five minutes left in the first quarter. Go for it probability: 2.9%
- Minnesota successfully went for it on fourth-and-4 at its own 31-yard line during Week 4 against Chicago. The Vikings were trailing by 16 with two minutes left in the third quarter. Go for it probability: 3.1%
- New England unsuccessfully went for it on fourth-and-7 at the Kansas City 27-yard line during Week 14. The Patriots were trailing by 10 with seven minutes left in the second quarter. Go for it probability: 3.1%
- Los Angeles Chargers unsuccessfully went for it on fourth-and-goal from the Minnesota 15-yard line during Week 15. The Chargers were down 15 points at the start of the fourth quarter. Go for it probability: 3.3%
- Chicago unsuccessfully went for it on fourth-and-9 at the Los Angeles Rams' 31-yard line during Week 11. The game was tied with nine minutes left in the first quarter. Go for it probability: 3.8%
- Baltimore successfully went for it on fourth-and-1 at its own 29-yard line during Week 15 against the New York Jets. The Ravens were up 21 points with two minutes left in the third quarter. Go for it probability: 4.1%
- Buffalo unsuccessfully went for it on fourth-and-10 at the Philadelphia 29-yard line during Week 8. The Bills were down 11 points with one minute left in the third quarter. Go for it probability: 4.9%
The most conservative decision according to our model? During Week 1, the Pittsburgh Steelers chose to kick a field goal on a fourth-and-goal from the New England one-yard line, when trailing by 20 points. Our model estimates that a typical team would have gone for it 95.2% of the time.