In determining cost to the retailer and cost to the wholesaler the secretary of revenue or a court shall receive and consider as bearing on the good faith of such cost, evidence tending to show that any person complained against under any of the provisions of this chapter purchased cigarettes, with respect to the sale of which complaint is made, at a fictitious price, or upon terms, or in such a manner, or under such invoices, as to conceal the true cost, discounts or terms of purchase, and shall also receive and consider as bearing on the good faith of such cost, evidence of the normal, customary and prevailing terms and discounts in connection with other sales of a similar nature in the trade area or state.
SDCL 37-10-24