Joint utility sales expenses shall be allocated among utility departments on the basis of the directly assigned sales expenses; provided, however, that deviation from such procedure may be made in instances where the activities of sales personnel do not conform with the distribution of directly assignable expenses.
Wis. Admin. Code Public Service Commission PSC 103.04
The entire cost of sales expenses applicable to merchandising operations must be charged to account 416, costs and expenses of merchandising, jobbing, and contract work.