Oregon Revised Statutes Public Officers and Employees § 240.165

(1) The administrative expenses and costs of operating the Personnel Division shall be paid by the various divisions of the service in the state government. To establish an equitable division of the costs, the amount to be paid by each division of the service shall be determined in such proportion as the service rendered to each division of the service bears to the total service rendered by the Personnel Division.

(2) The Personnel Division, at such times as its administrator deems proper, shall estimate in advance the expenses that will be incurred during a given period of not to exceed six months and, upon approval by the Director of the Oregon Department of Administrative Services, the division shall render to each division of the service affected thereby an invoice for its pro rata share of such expenses. Each division of the service shall pay such invoice as an administrative expense of that division of the service from funds or appropriations available to that division of the service in the same manner as other claims against the state are paid. If the estimated expenses in the case of any division of the service are more or less than the actual expenses, the difference shall be reflected in the next following estimate of expenses and invoice for that division of the service.