The Best Defense in NFL History? (My Project)

[footbrawl]

As the Superbowl approaches and Seattle has another good shot to repeat, I've heard a lot of claims about how they are possibly in the discussion for greatest of all time. This also includes Seattle defensive lineman Michael Bennett bluntly stating that they are the greatest of all time. I have a love for statistics so I decided to create a formula to make a straightforward list. My goal was to see who lived up to the hype statistically in their time and what they accomplished.


The Formula

Spoiler

I began by picking nominees of course. I began with 25 of the defenses always in the argument for GOAT. After I compiled those, I found statistics for the best all time defenses. I also made sure to have 10 teams from each decade (only 5 from '1960s and 2010s'. I did not allow teams before the first Super Bowl.

I purely looked at Points Allowed Per Game and Yards Allowed Per Game. My biggest conflict was finding an equal statistical look for different time periods. So I subtracted the team's averages that particular year from the league's average that season. The point difference favored the older teams as the yards difference favored the newer teams.

I arranged all 50 teams by the best to worst average differences. Each team's ranking both times were averaged out to give them an overall rank. The top 35 went on to the final stage.

At the final stage, the 35 teams were re-ranked on the average differences. Now, I included another factor that counts just as much as the stats, which was their accomplishments. Superbowl winners were ranked first, runner-ups 17th (ties for number one), and so on.

Finally, I added their point difference average ranking, their yards difference average ranking, and their accomplishment ranking (twice to count as half) and made an overall average/score. The final score decided their final rankings.

Honorable Mentions

25. 1999 Jacksonville Jaguars
Accomplished: Lost AFC Championship
Yards Difference: +47.9
Points Difference: +7.2

24. 1971 Minnesota Vikings
Accomplished: Lost Divisional Playoff Game
Yards Difference: +42.5
Points Difference: +9.5

23. 2006 Baltimore Ravens
Accomplished: Lost Divisional Playoff Game
Yards Difference: +58.0
Points Difference: +8.1

22. 2001 Pittsburgh Steelers
Accomplished: Lost AFC Championship
Yards Difference: +59.0
Points Difference: +7.0

21. 1973 Oakland Raiders
Accomplished: Lost AFC Championship
Yards Difference: +59.6
Points Difference: +7.0


The Top NFL Defenses of All Time

20. 1968 Baltimore Colts
Accomplished: Lost Super Bowl
Yards Difference: +54.1
Points Difference: +7.2
The 1960's-1970's Baltimore defenses were ranked highly many times. Apparently Johnny Unitas wasn't the only person behind their long term success. Their defense held its own against those like Green Bay.

19. 1986 Chicago Bears
Accomplished: Lost Divisional Playoff Game
Yards Difference: +66.1
Points Difference: +8.8
The first of two 1980's defense that made it. This was the year after they had one of the best seasons in NFL history. If they had done better in the playoffs they would have been ranked much higher.

18. 2010 Pittsburgh Steelers
Accomplished: Lost Super Bowl
Yards Difference: +59.2
Points Difference: +7.5
One half of two great defensive squads that made the list. They tested out above average in every spot and would've been much higher if not for Aaron Rodgers and the Packers.

17. 1990 New York Giants
Accomplished: Won Super Bowl
Yards Difference: +45.7
Points Difference: +6.9
I actually hated putting them on the list. Their differences had them barely make the first cut and their Super Bowl success shot them into the 17th spot. Regardless, they did have a hell of a defense behind LT and Carson.

16. 2000 Tennessee Titans
Accomplished: Lost Divisional Playoff Game
Yards Difference: +81.1
Points Difference: +8.8
Surprisingly, this is not the same year that they went to the Super Bowl. If it were, they'd been top ten easily. Them, along with the Ravens, put up differences that hadn't been seen since the early 70's.

15. 1970 Minnesota Vikings
Accomplished: Lost Divisional Playoff Game
Yards Difference: +81.6
Points Difference: +9.1
I shame myself for not realizing how good the Purple People Eaters were and how exactly they made it to four Super Bowls. They, as you'll see, have the most defenses in one span appear here. Not including a few that almost made the cut.

14. 1996 Green Bay Packers
Accomplished: Won Super Bowl
Yards Difference: +56.6
Points Difference: +7.3
Brett Favre had some help I guess. They had above average numbers (in terms of all time defenses) and were able to win throughout the playoffs. The 90's were not really heavy in defenses.

13. 1975 Los Angeles Rams
Accomplished: Lost NFC Championship
Yards Difference: +71.0
Points Difference: +11.0
The Fearsome Foursome, like the Purple People Eaters, had many top defenses all time, but this was their finest year. One of only a few teams to have differences of 70+ and 10+. Never could produce in nut cutting time.

12. 2014 Seattle Seahawks
Accomplished: Won Super Bowl (Theoretically)
Yards Difference: +81.0
Points Difference: +6.7
Of course, this is if they win it all. Michael Bennet does have a point when calling them one of the best. In a time where the rules favor the offense, they manage to shine among others. They have the sixth greatest yards difference ever.

11. 1972 Miami Dolphins
Accomplished: Won Super Bowl
Yards Difference: +55.9
Points Difference: +8.1
The no name defense finished how I expected. One of the best, but not in the competition for number one. They were the only undefeated team in NFL history for a reason.

10. 1966 Green Bay Packers
Accomplished: Won Super Bowl
Yards Difference: +10.1
Points Difference: +41.8
The very first Super Bowl winners had a great defense to compliment a great offense. We all know the loads of Hall of Famers on this squad, but I did not realize they're statistical greatness. One of only four teams with a +10 point difference.

9. 1971 Baltimore Colts
Accomplished: Lost Super Bowl
Yards Difference: +82.1
Points Difference: +9.4
The best year for the legendary Colts defense was '71. Though they lost another Super Bowl, their numbers are at the best of all time. They have the third best yards difference ever.

8. 1969 Minnesota Vikings
Accomplished: Lost Super Bowl
Yards Difference: +105.4
Points Difference: +11.4
Hands down the greatest regular season defense of all time. If they had won a Super Bowl they would be in the number one spot overall. So underrated. Both number one in yards difference and points difference ever. The next closest for yards in that era is 23 yards lesser.

7. 1969 Kansas City Chiefs
Accomplished: Won Super Bowl
Yards Difference: +73.5
Points Difference: +8.3
Another legendary defense that lived up to the hype. The '68 squad improved on their pass defense and became one of the best of all time. Bobby Bell and Willie Lanier. Ridiculous numbers.

6. 1976 Pittsburgh Steelers
Accomplished: Won Super Bowl
Yards Difference: +65.7
Points Difference: +9.3
And here comes the controversy. I was actually happy that the teams argued for the best made it to the top. However, people will argue if the Steel Curtain should be penalized for possibly a statistical bias. In the defense of modern teams, the rules favored the defense in this time.

5. 1985 Chicago Bears
Accomplished: Won Super Bowl
Yards Difference: +71.0
Points Difference: +9.1
Another legendary squad. The only 80's team on the list (aside from the '86 team). Both numbers rank very high and there's no doubt they are one of the best defenses ever.

4. 2013 Seattle Seahawks
Accomplished: Won Super Bowl
Yards Difference: +74.9
Points Difference: +9.0
I wanted to argue, but I couldn't. Their numbers match and pass up other legendary defenses. With the rules favoring the offense, and during the best offensive year in NFL history, they made their mark. Capping it off by beating the best statistical offense ever easily in the big one.

3. 2008 Pittsburgh Steelers
Accomplished: Won Super Bowl
Yards Difference: +90.0
Points Difference: +8.1
Surprised? I was too. Full of great players such as Polamalu, Harrison, Farrior, Taylor, Hampton, and Kiesel, they had the second best yards difference ever. They match up in every category.

2. 2000 Baltimore Ravens
Accomplished: Won Super Bowl
Yards Difference: +71.5
Points Difference: +10.4
A much talked about defense that lived up. Considering their playoff dominance, this squad put up numbers not seen for three decades. The best point difference of the modern times along with several guys going to Canton.

1. 2002 Tampa Bay Buccaneers
Accomplished: Won Super Bowl
Yards Difference: +75.6
Points Difference: +9.5
Tony Dungy must be really mad now. The team he built came to a peak putting up two top ten averages all time as well as dominating the playoffs for a win. Numerous Hall of Famers will/have come from this team. They did this against all rules changes and without a doubt, in this system at least, are the greatest of all time.


Extra Awards

Most Underrated
2008 Pittsburgh Steelers - Through all my research of the best all time defenses I never saw this team. They finished number three all time, and put up all time differences. 235 yards allowed per game is unheard of in the modern NFL.

Most Overrated
1977 Denver Broncos - Better known as the Orange Crush, their stats ranked almost last in both categories when compared to other legendary teams. The low league averages could've been the cause... regardless, they didn't live up like most other teams.

Unsung Hero
1977 Atlanta Falcons - Who? Exactly. This team didn't even make the playoffs. However, they have the record for least points per game allowed ever (9.2). Maybe the low league average hurt them in the rankings as they narrowly missed the honorable mentions.

Best Decade
1970's - Though the 70's and 00's both had seven teams in the top 25, I give the edge to the 70's. The dynasties of the Colts, Steelers, Vikings, Raiders, and Rams haven't been matched in their long term success. I realize how free agency has affected this, but regardless, their dominance over a decade is amazing.

Best Run
60's/70's Minnesota Vikings - I started this project knowing only a little bit about Bud Grant and his Purple People Eaters and I end it with a newly found respect. He was four wins away from being considered the best ever, period. Look it up yourself, season after season they didn't place just place the best that year, but all time. So would you rather take the one hit Buccaneers or the long term Vikings? Who really is the best ever?

Afterthoughts
This was just a small project of mine and I think it turned out well. I was glad that the mostly talked about defenses finished high. I'm not sure how to feel about the top four being all modern teams. Though I do think the rule changes have made defenses become better, there's no doubt that the level of toughness and grittiness of the old days can't be matched. I also know the flaws within the system putting such focus on PAPG and YAPG. Also, how one league average change from year to year can really help or hurt a team's chance. All aside, I think it was successful.

[footbrawl]

I apologize for the small text. Normal text made it look messy.

[kehlis]

I appreciate the work and by no means intend to discount it but there are a lot of flaws in the methods and it starts with just arbitrarily choosing teams to create your formula with and there can't be a stage in any calculation where teams "move on and advance."

To show the effectiveness of a formula you need to be able to rank teams based on one set formula. Can't add things once teams get to the "second round".


And when talking about statistically "bests" you can't include accomplishments in any formula. That has to be left out.

[footbrawl]

Quote: Originally Posted by kehlis

I appreciate the work and by no means intend to discount it but there are a lot of flaws in the methods and it starts with just arbitrarily choosing teams to create your formula with and there can't be a stage in any calculation where teams "move on and advance." To show the effectiveness of a formula you need to be able to rank teams based on one set formula. Can't add things once teams get to the "second round".

No offense taken. As I say in the Afterthoughts, I realize the flaws in the system. I realize what you're saying about adding things in through stages. I felt like too many teams would jump really high solely because they won the Super Bowl.

My goal was to get to 35 of the best statistical teams ever because there is no bias. Then, once I got those teams I'd separate them by how they performed in the post season. Because I think post season performance is what separates great teams from the very best.

[SPTO]

Ehhhh As Kehlis says the methodology seems a bit suspect. I also think that there should be some kind of combination of an eye test in there. I know that's not possible for all the teams but the numbers alone don't always tell the full story.

[JayBee74]

I applaud your effort. A lot of great defenses there. After hearing Rex talk, 2015 Buffalo might get the top spot next year.

[footbrawl]

Quote: Originally Posted by SPTO

Ehhhh As Kehlis says the methodology seems a bit suspect. I also think that there should be some kind of combination of an eye test in there. I know that's not possible for all the teams but the numbers alone don't always tell the full story.

I wish there was too. Stats were my only way of really getting a straight answer. But football isn't something straightforward. I may redo another formula in the future with everyone's suggestions.

Quote: Originally Posted by JayBee74

I applaud your effort. A lot of great defenses there. After hearing Rex talk, 2015 Buffalo might get the top spot next year.

Hopefully Rex gets it right. If not, it'll be a huge waste of talent with the guys on that defense.

[kehlis]

Quote: Originally Posted by footbrawl

I wish there was too. Stats were my only way of really getting a straight answer. But football isn't something straightforward. I may redo another formula in the future with everyone's suggestions.

Problem is you can't have both.

You either have a strict formula that can be applied the same to every team or you have a discussion that involves every team with all the factors you've mentioned (success, eye test, etc...) when there really is no answer.