My part timers only pay for stats if it falls on their scheduled day. I usually raise rates when I get a new child, the existing parents continue at the old rate. I have been in this business for 20 years and have only raised rates for everyone at the same time once or twice. I am currently charging $38 per day for full time and $40 for part time. When I do a rate increase, it is usually a $1 or $2 per day. Hope this helps.