Each debtor shall be charged for administration expenses, and the amounts charged shall be credited to the appropriation account under s. 20.566 (1) (h). The department may set off amounts charged to the debtor under this subsection against any refund owed to the debtor, in the manner provided in sub. (3). Annually on or before November 1, the department shall review its costs incurred during the previous fiscal year in administering setoffs and reductions under this section and shall adjust its subsequent charges to each debtor to reflect that experience.