Assume a company has only one service department and one operating department. The service department’s budgeted and actual variable costs for the period were $80,000 and $84,000, respectively. The budgeted units of service provided to the operating department were 40,000 units. The company properly assigned $82,000 of the service department’s variable costs to the operating department. 

What must have been the actual units of service provided by the service department to the operating department?