Sec. 5. (a) Subject to subsection (b), the amount of adoption subsidy payments under this chapter may not exceed the amount that would be payable by the department for the monthly cost of care of the adopted child in a foster family home at the time the adoption subsidy agreement is made or the subsidy is payable under the terms of the agreement, whichever is greater.
(b) In the case of an adoptive parent of a child with special needs that is in the therapeutic foster care or therapeutic plus category of supervision, the amount of adoption subsidy payments under this chapter may not be less than an amount equal to fifty percent (50%) of the per diem rate determined by the department for the:
(1) therapeutic foster care; or
(2) therapeutic plus;
category of supervision, whichever is applicable, that would be payable by the department for the monthly cost of care of the adopted child in a foster family home at the time the adoption subsidy agreement is made or the subsidy is payable under the terms of the agreement, whichever is greater.