The department shall pay each human service zone’s expenses for administering human services for calendar years after December 31, 2019, based on the payment amount calculated for each human service zone under chapter 50-35. The commissioner of the department or commissioner’s designee shall authorize expenditures from the human service finance fund to reimburse the department for the department’s costs of providing human services that historically have been provided by a county or human service zone, or for a new service or program based on federal or state law.