NFL teams seeking quarterbacks this offseason will naturally wonder how many victories Kirk Cousins might add to their bottom line. The projection is fascinating, but not complicated.
We carried out a similar exercise when Carson Palmer left the Oakland Raiders for the Arizona Cardinals in 2013. The numbers projected Palmer's addition would be worth about three additional victories per season for the Cardinals if Palmer played as well as he'd played in 2012. Palmer played even better than that, helping Arizona go from 5-11 to 10-6.
The answers are well within our grasp.
First, a question: Which Kirk Cousins is his next team getting? Will it be the Cousins who trails only Tom Brady, Matt Ryan, Aaron Rodgers, Ben Roethlisberger and Drew Brees in Total QBR from 2015 to 2017 among quarterbacks who started all three seasons? Or, will it be the Cousins who ranked 15th in QBR last season, behind Blake Bortles, Marcus Mariota and Tyrod Taylor?
In that regard, the question Vikings coach Mike Zimmer raised regarding Case Keenum -- "Is he the guy that played for the Rams or is he the guy that played for us?" -- applies in principle to Cousins as well. The difference is that Cousins has performed at a higher level over multiple seasons, whereas Keenum is a one-year wonder until proved otherwise.
Because of that, we compared the three-year production for Cousins against the quarterback production for Minnesota and other QB-needy teams over the same 2015-17 span. Then, we looked at what the 2017 version of Cousins would add to the QB-needy teams. Finally, we looked at what the 2015-17 version of Cousins would've done for those same teams in 2017. This gave us a range of additional wins for each team.
Note: For more on how many more wins Cousins would add to the Cardinals, Broncos, Vikings, Jets, Browns, Jaguars, Dolphins and Giants in each of those three scenarios -- as well as how we got to those conclusions -- click here.
A team-by-team overview of Cousins' potential impact
1. Cleveland Browns (+3.1 to +4.6 victories)
The Browns' 41.0 QBR over the past three seasons is the NFL's second worst, behind 39.2 for the Los Angeles Rams. Cleveland has ranked 32nd on defense and 28th on special teams since 2015. That is why the Browns have won only four total games in that span, far worse than the 6.6 per season we would have expected based on their QBR alone. Cousins would provide a significant upgrade, but this team isn't winning anything of significance without improved play in other areas as well.
2. Denver Broncos (+2.6 to +3.8 victories)
Cousins would certainly provide an upgrade for the Broncos, but if age catches up to their defense and the offensive support remains lacking, the payoff might be disappointing.
Denver has been here before. The 2011 Broncos averaged 46.3 in QBR, which equates to 7.4-win QB performance. Peyton Manning produced at a 12-win level the following year (74.9 average QBR). Manning's addition and the Broncos' simultaneous improvement on defense helped the Broncos jump from 8-8 to 13-3. Cousins is not Manning, and the Denver defense might be trending in the opposite direction, although after especially dispiriting QB play last season, positive change could re-energize Von Miller & Co.
3. Miami Dolphins (+2.2 to +3.3 victories)
The projected improvement range might need some tweaking in the Dolphins' case simply because their quarterback situation has been jumbled enough to make recent baselines less relevant.
Cousins at his worst (2017) equated to 8.5 expected wins, compared to the 7.6-win expectation for the 2016 version of Ryan Tannehill (47.5 average QBR). That's an improvement, but not a dramatic one. The gap widens to about two full games if we use the 60.2 QBR Cousins from the 2015-17 seasons. Do the Dolphins think they can get that level of performance from Tannehill?
Miami has had success in the veteran quarterback market previously. The addition of Chad Pennington before the 2008 season produced a 4.2-game improvement at the position as Miami jumped from a 37.5 average QBR (2007) to a 63.7 average QBR (2008). That upgrade, coupled with significant improvements on defense, helped the Dolphins jump from 1-15 to 11-5.
4. New York Giants (+2.0 to +3.1 victories)
The 60.2 QBR Cousins adds nearly 2.2 victories per season to the Giants, which is roughly the same as he would add to the Jets. That's right, the Eli Manning-led Giants have a 46.6 average QBR since 2015, which is a tick below the 46.7 average for the Jets.
The Giants' offensive line and receiver situation were horrendous last season, making it tougher to evaluate Manning's performance. The Giants' 2017 QBR baseline could be misleading as a result.
5. Arizona Cardinals (+0.8 to +3.1 victories)
The relatively modest gain in victories on the low end could be misleading. This calculation was made using Carson Palmer's production from the past three seasons in Arizona. Palmer has retired. For the Cardinals, a modest improvement from Palmer could represent a massive improvement from other quarterbacks that could be available to Arizona.
The Cardinals learned in 2012 just how bad the bottom of the QB barrel can be. Their 27.1 average QBR that season projected to 4.3 victories (the team went 5-11), leading Arizona into the market for a veteran quarterback. Palmer produced an immediate 4.1-victory improvement with a 53.1 average QBR in 2013 as Arizona improved to 10-6.
A torn ACL sidelined Palmer in 2014, and Arizona's average QBR dipped to 49.6, which equates to 7.9 projected victories (Arizona went 6-0 with Palmer and 5-5 without him, helped along by a defense that ranked seventh in ESPN's efficiency metric). Palmer returned better than ever in 2015, producing a 72.8 average QBR that projected to 11.6 victories (Arizona went 13-3).
6. New York Jets (+1.2 to +2.3 victories)
The Jets have the roster spot, cap space and cash flow to make a run at Cousins, and the numbers say he'd be worth at least a couple of victories per season. However, Cousins' average QBR from last season (53.3) is about the same as the 50.2 average that Josh McCown posted, so there's a chance Cousins would not provide the anticipated bump.
The Jets have added big-name veteran QBs previously. They improved from 4-12 to 9-7 after adding Brett Favre for the 2008 season. Favre himself provided only a modest upgrade in QBR, worth about 1.2 additional victories. The Jets improved quite a bit statistically on both sides of the ball after a free-agent spending spree that landed Alan Faneca, Calvin Pace, Damien Woody, Ty Law, Bubba Franks and Tony Richardson.
7. Jacksonville Jaguars (-0.5 to +1.7 victories)
Blake Bortles improved last season and actually had a higher QBR for the Jaguars than Cousins had for the Redskins, which is why the low-end projection would have Jacksonville losing one-half victory from the QB position. The high-end projection compares the Jaguars' 2015-17 average QBR (49.6) to the 60.2 for Cousins over the same period. In the end, the Jaguars stayed the course with Bortles at a lower price than Cousins will command, an understandable decision.
8. Minnesota Vikings (-1.4 to +0.7 victories)
While the Vikings seem to be the favorite to land Cousins at this point, the numbers say they might not be getting a dramatic upgrade from the position. They would be getting a measure of long-term stability from a player who is more established than Keenum, and therefore less likely to suffer a dramatic drop in performance. Cousins represents a safer bet for a team that has been walking a year-to-year tightrope at the position.
Adding Favre for the 2009 season produced a massive QBR gain for Minnesota equating to 4.6 additional projected victories. The team's actual gain was two victories, from 10-6 to 12-4. The Vikings went 13-3 last season, leaving little room for improvement in the standings.
Inside the numbers
What the 2015-17 version of Kirk Cousins would add to the 2015-17 versions of QB-needy teams
The Broncos make for an interesting study. Their QBR over the past three seasons equates to seven expected victories per season with average support from teammates on offense, defense and special teams. Cousins' QBR over the same period would equate to 9.6 expected victories. Therefore, the way Cousins performed from 2015 to 2017 would add about 2.6 victories per season over how the Broncos' quarterbacks performed over the same period.
The gains for Minnesota would be much smaller, about 0.7 victories per season over what Teddy Bridgewater, Sam Bradford and Keenum provided over the past three seasons. Teams such as the Browns, Dolphins, Giants and Jets would seem to gain much more:
ESPN's Stats & Analytics department made these calculations simple. Twelve seasons of Total QBR data shows that a team with a 50 QBR will win about 50 percent of the time, and so on. With these win rates firmly established, we can project the differences in victory totals for different quarterbacks based on their performance levels over time.
Cousins averaged a 60.2 QBR during his three full seasons as Washington's starting quarterback (49 games, counting playoffs). This included two seasons with a strong offensive line, above-average weaponry and optimum offensive coaching, followed by a third season notable for personnel losses, increased injuries and Sean McVay's departure as offensive coordinator.
If we think Cousins will perform about as well in the future as he has performed on average since 2015, we can project what impact he could make on another team using that baseline.
Because QBR correlates with win rate, we simply convert Cousins' 60.2 QBR to a percentage and multiply by 16 games -- 60.2 percent of 16, in other words -- to produce an expected annual victory total (9.6). This total assumes a typical supporting cast, including on defense and special teams. The Redskins were only 22nd in defensive efficiency and 24th in special-teams efficiency from 2015 to 2017. This explains why Washington won 24 games over the past three seasons, nearly six fewer than we would have expected from Cousins' QBR alone.
An especially strong defense allowed Denver to average 8.7 victories per season since 2015 despite its seven-win QBR. If the Broncos were to maintain that defensive level, Cousins could conceivably vault them into the 12-win range. Of course, there are no guarantees.
What the 2017 version of Kirk Cousins would add to the 2017 versions of QB-needy teams
Cousins might not be able to maintain his three-year 60.2 QBR average, especially if he plays for teams with unusually weak supporting casts on offense. Cousins' average QBR slipped from 63.4 (2015) and 63.7 (2016) with very good support to a middling 53.4 last season with poor support.
Inserting Cousins' diminished 2017 production into the Broncos' framework would add about 1.5 victories per season over their 2015-17 QB baseline and 2.7 victories over what they got from the QB position last season -- nice bumps, but not necessarily a ticket to the Super Bowl.
Below we see how many victories per season the 2017 Cousins (with his 15th-ranked QBR) would add to the same teams listed in the first table. We use those teams' 2017 QBRs as the baseline for the calculation, instead of the figures from 2015-17. Note that the Vikings would actually lose 1.4 expected victories from the QB position with the 2017 Cousins replacing the 2017 Keenum. Cleveland, Denver, Miami, the Giants and Arizona would all gain at least two victories. The Jets would gain 1.2 victories, while the Jaguars would be about the same.
What the 2015-17 version of Kirk Cousins would add to the 2017 versions of QB-needy teams
Here we assume Cousins will perform about as well in the future as he has performed over the past three seasons. We then compare this better-case-scenario Cousins to the production teams got from their QBs last season (not over the past three seasons).
The Browns would be adding 4.6 victories from the QB position, with the Broncos (3.8), Dolphins (3.3), Giants (3.1) and Cardinals (3.1) all adding at least three victories.