Does defense affect a QB's record?

The following is a chart of QBs and their win percentages based off of how many points they had to score to win games.  I have been a big proponent of the fact that defense matters when it comes to QB's and their records.  So I picked 10 QBs.  They had to have at least 120 starts.  I sorted them by scores of the games they started.  Then split them out into 4 categories.   Having to score 18 points or less to win, 19-25, 26-32  and 33+.  As you can see, the win percentages drop dramatically when QBs have to score more than 33 points to win a game.  I also took the total number games played under each score as a percentage of total games played.  This is labeled as PTG.  Ties are counted as half a game. 

For example QB A  had 76 total games where he only had to score 18 points to win. That made up 48% of all the games he played. While he only had 15 game where he had to score 33+ points to win. Making up only 9% of total games.  On the right is the percentage of games won when they had to score 25 points or less to win. 84% of QB A's wins came when he only had to score 25 points or less to win. And that makes up 73% of his total games.  

I will tell you this about the QB's on the list. There are 5 non SB QB's and 5 SB winning QB's on the list.  And no, Rodgers, Favre and Brady are not on it. 


18 pts Win % PTG        19-25 pts  Win %   PTG      26-32  Win %   PTG     33+    Win %  PTG       Games < 25 pts TW    WP      TG
A 66  10 87% 48%         19   22   46%     26%      12   16  43%   18%      4   11   27%    9%         84%   73%        101   63%    160
B 42   7 86% 33%         22   20   52%     28%       9   22  29%   21%    3.5 22.5   13%   18%         84%   61%       76.5   52%    148
C 60   9 87% 30%            40.5 33.5   55%     32%      22   38  37%   26%      1   29    3%   13%       81%   61%      123.5   53%    233
D      104  17 86% 50%              27   18   60%     19%      14   27  34%   17%      2   33    6%   14%         89%   69%        147   61%    242
E 69  17 80% 40%         22   29   43%     24%       8   30  21%   18%      3   35    8%   18%         89%   64%        102   48%    213
F 68   6 92% 31%         33   34   49%     29%      12   32  27%   19%      4   46    8%   21%         86%   60%        117   50%    235
G 75  14 84% 49%         12   25   32%     20%      10   27  27%   20%      1   18    5%   10%         89%   69%         98   54%    182
H 105  8 93% 47%         45   21   68%     27%      13   25  34%   16%      4   22   15%   11%         90%   74%        167   69%    243
I 43  11 80% 28%              30   21   59%     27%    11.5 34.5  25%   24%      5   35   13%   21%         82%   55%       89.5   47%    191
J 68   8 89% 51%         18   15   55%     22%       7   14  33%   14%      1   17    6%   12%         91%   74%         94   64%    148

Cous    33   3 92% 25%              26   14   65%     28%      14   25  36%   27%      2   25    7%   19%         79%   54%         75   53%    142


As an added bonus I put Cousins on the bottom. Mainly because people would ask where he stands.  46% of all his games he has to score over 25 points to win.  And only one other QB comes close to 18 points or less games. 

But defense doesn't matter.  Right?

Criticize away.