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While the San Francisco 49ers offense deals with a quarterback “issue” that keeps grabbing the headlines, the team’s defense continues with a “business as usual” attitude that has the unit at the top of the NFL STOP Factor rankings.

The 49ers defense is just percentage points ahead of the Chicago Bears defense in this weekly ranking. The 49ers have stopped their opponents from scoring on 84 of 113 possessions, a STOP Factor of 74.3. The Bears’ “D” is ranked second with a 74.0 rating.

One quick note: Looking at the records  of teams that are listed in this rankings top five, these five teams have a combined win-loss record of 38-16-1, a winning percentage of .700. The five teams listed in the bottom five of the STOP Factor rankings are a combined 16-39, a .291 winning percentage.

A strong defensive unit wins games!

(The STOP Factor is based on the premise that it is the defense’s job to stop their opponents from scoring on each possession. To get a team’s STOP Factor, you divide the number of times a defense stops the offense from scoring – offensive unit TD or field goal – by the number of total possessions by the opposition.)

Following is each NFL teams’ STOP Factor. Listed is how many times each team stopped the opponents from scoring, the number of possessions their opponents had, and the percentage of possessions that each team prevented the other team from scoring (stats are through Week 12 games; games for Thanksgiving Day are not included in this week’s totals).

Team, Opponents’ scoreless possessions/opponents’ possessions, STOP percentage

1. San Francisco 74.3 (84 stops in 113 possessions)

2. Chicago 74.0 (97 stops in 131 possessions)

3. Houston 72.8 (99 stops in 136 possessions)

4. Arizona 70.2 (92 stops in 131 possessions)

5. Denver 70.1 (89 stops in 127 possessions)

6. Seattle 70.0 (77 stops in 110 possessions)

7. Cleveland 68.9 (91 stops in 132 possessions)

8. Tampa Bay 66.9 (83 stops in 124 possessions)

9. San Diego 66.7 (78 stops in 117 possessions)

10tie. Miami 66.4 (83 stops in 125 possessions)

10tie. Pittsburgh 66.4 (75 stops in 113 possessions)

12. Atlanta 66.1 (76 stops in 115 possessions)

13. New England 65.6 (80 stops in 122 possessions)

14. Cincinnati 65.3 (79 stops in 121 possessions)

15. New York Giants 64.7 (75 stops in 116 possessions)

16. Baltimore 64.6 (82 stops in 127 possessions)

17. Green Bay 63.4 (78 stops in 123 possessions)

18. Minnesota 62.5 (75 stops in 120 possessions)

19. St. Louis 62.4 (73 stops in 117 possessions)

20. Detroit 61.9 (73 stops in 118 possessions)

21. New York Jets 61.3 (73 stops in 119 possessions)

22. Dallas 61.1 (69 stops in 113 possessions)

23tie. Indianapolis 60.2 (68 stops in 113 possessions)

23tie. Philadelphia 60.2 (71 stops in 118 possessions)

25. Washington 58.5 (72 stops in 123 possessions)

26. New Orleans 57.5 (69 stops in 120 possessions)

27. Kansas City 57.0 (65 stops in 114 possessions)

28. Buffalo 56.0 (65 stops in 116 possessions)

29. Jacksonville 55.3 (68 stops in 123 possessions)

30. Carolina 54.3 (63 stops in 116 possessions)

31. Tennessee 53.8 (63 stops in 117 possessions)

32. Oakland 51.6 (65 stops in 126 possessions)

Biggest gainers this week: New York Giants (up four spots this week); Pittsburgh (up four spots this week); Cincinnati (up three spots this week); Cleveland (up three spots this week); St. Louis (up three spots this week).

Biggest losers this week: Green Bay (down seven spots this week); Atlanta (down five spots this week); Dallas (down four spots this week).

Average league STOP Factor (through Week 12): 63.5

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