I'm in the Hamilton region and I charge a little differently. I don't charge for sick, stat or my vacation. I also allow clients to take one week off unpaid, but if they take more then 1 week off then they need to pay for the space.
I've thought of raising my rates 2.00 a day but it seems like such an odd number. I also have trouble changing my policies from when they started as I feel that they started with me for these reasons, to change things now would be like breaking a promise. But that's just me.
If I were to put a sick day policy into place and charge for everything after 3 or 5 sick days then I would want to consider the fact that I will have to chase for that money. No one is going to keep track of that but me. So it will be me sending the email that says... you owe me! And that would make me feel like I was nickle and diming. That's just my comfort level.
If I needed to raise fees to cover vacay or sick, then I would raise a few dollars a day and put that money aside. I think it looks much better to say that I don't charge when your child is not here then to start having to track it all.