Here is the attendance index for each team (taken simply as the fans per home game, divided by the MLB average, for that season), averaged from 1969-2006. Number 1 is the Dodgers, who had 61% more fans than average, on average (while playing .534 ball in that time frame):
Att_Index win_percent years team ... 0.86 0.501 38 CHA
That’s 86%. 14% below average.
How about when the Sox play under .500?
Att_Index win_percent years team
...
0.72 0.45 18 CHA
That’s 72%. 28% below average.
and when the Sox play over .500:
Att_Index win_percent years team
...
0.98 0.548 20 CHA
That’s 98%. Just 2% below average.
So, keep winning and the fans will be coming Kenny!
