(1) In calculating the administration fund assessment the department shall:
(a) deduct any outstanding credits a plan No. 1 insurer may have to arrive at the final amount due from that insurer;
(b) deduct any outstanding credits the plan No. 3 insurer may have for old fund claims to arrive at the final amount due with respect to old fund claims; or
(c) deduct the aggregate of any outstanding credits that plan No. 2 insurers and that the plan No. 3 insurer (with respect to plan No. 3 new fund claims) may have to arrive at the final amount due via the administration fund assessment premium surcharge.