Finance Charge set up - flat percentage on over due invoices over a certain amount

We have a request to set up a Finance Charge ID that will bill a flat 10% of the balance of all overdue invoices that are above $100.   We are able to set it up with the 10% and excluding invoices less than $100, but it calculates on an annualized basis, therefore giving us a much lower finance charge than we would like.    For example, if there are two $150 invoices outstanding and three $50 invoices outstanding, then we would want the calculation to ignore the $50 invoices, and calculate 10% of the $300 total of the two outstanding $150