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With two weeks remaining in the NFL regular season, the Chicago Bears defense has taken the lead in the weekly NFL Stop factor rankings. The Bears “D” jumped over the San Francisco 49ers defense for first place in these rankings after the 49ers defense gave up 34 points in their win last Sunday night against the New England Patriots.

The surprising Seattle Seahawks, who host the 49ers tomorrow in Seattle, have moved in to second place in the rankings ahead of the 49ers.

(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 15 games).

Team, Opponents’ scoreless possessions/opponents’ possessions, Stop Factor percentage

1. Chicago 73.5 (119 stops in 162 possessions)
2. Seattle 72.9 (105 stops in 144 possessions)
3. San Francisco 72.7 (109 stops in 150 possessions)
4. Houston 72.1 (124 stops in 172 possessions)
5. Arizona 70.6 (120 stops in 170 possessions)
6. Denver 70.4 (114 stops in 162 possessions)
7. Cleveland 69.1 (114 stops in 165 possessions)
8. New York Jets 67.3 (107 stops in 159 possessions)
9. Cincinnati 67.1 (104 stops in 155 possessions)
10. Atlanta 66.9 (97 stops in 145 possessions)

11. New England 65.8 (106 stops in 161 possessions)
12. San Diego 65.6 (99 stops in 151 possessions)
13. Miami 65.1 (99 stops in 152 possessions)
14. Tampa Bay 65.0 (104 stops in 160 possessions)
15. Green Bay 64.7 (99 stops in 153 possessions)
16. Pittsburgh 64.6 (95 stops in 147 possessions)
17. Minnesota 64.3 (99 stops in 154 possessions)
18. Baltimore 63.0 (104 stops in 165 possessions)
19. St. Louis 62.7 (96 stops in 153 possessions)
20. New York Giants 62.5 (90 stops in 144 possessions)

21. Philadelphia 60.3 (91 stops in 151 possessions)
22. Washington 60.0 (93 stops in 155 possessions)
23. New Orleans 59.9 (94 stops in 157 possessions)
24. Detroit 59.6 (93 stops in 156 possessions)
25. Dallas 59.2 (84 stops in 142 possessions)
26. Tennessee 58.4 (90 stops in 154 possessions)
27. Indianapolis 58.1 (86 stops in 148 possessions)
28. Buffalo 57.0 (85 stops in 149 possessions)
29. Kansas City 56.3 (80 stops in 142 possessions)
30. Carolina 56.0 (79 stops in 141 possessions)
31. Jacksonville 55.2 (85 stops in 154 possessions)
32. Oakland 54.2 (84 stops in 155 possessions)

Biggest gainers this week: Atlanta (up five spots this week); Miami (up five spots this week).

Biggest losers this week: Buffalo (down six spots this week); Tampa Bay (down six spots this week).

Average league Stop Factor (through Week 15): 63.9

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