I think that would be a good assumption for your arena too but I'm a little hesitant because you have so few seats.
Have you raised the price this season or is the current price the same for the hole season?
You should be careful with the position you hold in your league because as i can see you have a very balanced league.Loosing 2-3 balls in the Fan Survey you may lose some of your seats even in you higher priced places(Courtside/Luxury).
But 10% usually pays off pretty nicely and even if you don't fill up all the seats you will not lose many and you will be compensated by the higher price.