Charge Model for Peek Usage

[hwdavidward]

I was looking over the charge models but I didn't see an obvious answer to the type of charge model I was looking for. I'd like to charge users based on my users peek usage for a month. That is I would like to upload the usage each day and charge them based on the day they used the most usage.

i.e. 

  Every day of the month the user uses 10 units except the 15th where they used 20. I would like to charge them a rate based on the 20 for the month.

Is this possible? If so how? 

David