There are always arguments about which teams have the most devoted fans. So why not attempt a mathematical measurement of fan loyalty?
What we have here is FDA. No, not the U.S. Food and Drug Administration. This is Fan Devotion Average.
What we want is a method of measuring which fan bases stick with their team, even in the midst of -- let's face it -- crummy seasons. So we take the average attendance, in this case for 2015, and divide it by the number of victories a team had.
Thus, if a team drew an average of 35,000 people and won 70 games, that would be a Fan Devotion Average of 500.0. As it turns out, that would be a terrific average. A team that won 80 games and had an average attendance of 24,000 would have a Fan Devotion Average of 300.0, which would be less than terrific.
Is this calculation weighed against teams with winning records? Yes, marginally, at least, because teams that are winning are supposed to draw massive audiences. The idea here is also to determine which fans stay with their teams in difficult times.
Still, the franchises with the best numbers here are those that combined winning with big crowds. The Dodgers and Giants are the prime examples. It is particularly difficult to compete against the Dodgers' average attendance of more than 46,000.

The clubs that make a particular impression here are the ones that had a down season on the field but still did admirably well at the gate. Notable teams in that category in 2015 included Cincinnati, Milwaukee, Boston, Colorado and Detroit -- in that order of finish in this calculation. Virtual standing ovations for each and every one of these fan bases are now in order.
Here are the top 15 MLB franchises in the order of finish in Fan Devotion Average for 2015. This is not meant as a commentary on the relative qualities of these organizations. It is merely one measurement of fan loyalty.
1. Dodgers: 505.2
2. Giants: 496.2
3. Reds: 466.7
4. Brewers: 461.2
5. Red Sox: 455.9
6. Rockies: 455.1
7. Tigers: 454.8
8. Yankees: 453.2
9. Angels: 437.6
10. Cardinals: 434.7
11. Padres: 410.4
12. Nationals: 389.7
13. Cubs: 371.5
14. Blue Jays: 371.0
15. Braves: 368.8

There are built-in historical variations. For instance, the Cubs would have been ranked higher in earlier seasons, when they were drawing very well but not winning much. But they can probably live with this one disadvantage of winning 97 games.
The Cardinals, with 100 victories, were the team most penalized for success in this approach. Again, this is a very small price to pay for that kind of success.