in my believe fanbase is a factor which is used in the calculation of the crowds entering your arena.
Then from my own experience:
Notice it is steadily growing when you perform well on average. You can see this by checking out your luxury boxes sales. At least in my case this is growing slow, but steady. (unless you highten your ticketprice ofcourse) because they are less depending on your wins or losses.
Except for the fanbase, which is the basic factor, there is also a factor of win/loss wich goes into the calculation, and has most effect on the lowest priced seats.
Do I dare write the next thing, ... hm, yes, let me go for it:
I'm taking another wild guess here, so don't ask me to show you where I got it, it comes out of my head:
basic crowd uses fanbasefactor, that is your crowd you will have for your next homegame in a certain percentage for every type of seat. Then , if you won your last game (or maybe it looks at last few games, effect get bigger if it was a TV game) you get extra crowds: a lot for lowest cost seats, many for second lowest cost sets, some or a few for the second highest cost seats, and none (or 1, or maybe a few??) for luxury boxes.
If you consistently get more wins than losses over a period of time, you fanbase will grow. If you perform badly and get more losses, your fanbase will probably shrink. I also think the division you play in, might have an influence on this growth, but I'm totally unsure of that.
It is just a theory, based on my experience so far. People who are interested could try to verify it, or might collect facts to break it down.
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