(b)__Beginning October 1, 1998, the department shall seek to achieve an aggregate rebate amount from all rebate agreements that is 6 percentage points higher than that required by subdivision (a), provided such rebates result in a net increase in the rebate revenue available to the elderly low-cost drug program.

(2)__Upon receipt of data from the department, the manufacturer shall calculate the quarterly payment.

(a)__If a discrepancy is discovered, the department may, at its expense, hire a mutually agreed-upon independent auditor to verify the manufacturer's calculation.

(b)__If a discrepancy is still found, the manufacturer shall justify its calculation or make payment to the department for any additional amount due.

(c) The manufacturer may, at its expense, hire a mutually agreed-upon independent auditor to verify the accuracy of the utilization data provided by the department.__If a discrepancy is discovered, the department shall justify its data or refund any excess payment to the manufacturer.

(d) If the dispute over the rebate amount is not resolved, a request for a hearing with supporting documentation must be submitted to the department's office of administrative hearings.__ Failure to resolve the dispute may be cause for terminating the drug rebate agreement and denying payment to the manufacturer for any drugs.

(3)__A prescription drug of a manufacturer that does not enter into an agreement pursuant to this paragraph is reimbursable only if the department determines the prescription drug is essential.

(4)__All prescription drugs of a manufacturer that enters into an agreement pursuant to this paragraph that appear on the list of approved drugs under the