IIF([后勤费基数] / [订单量] > [人工价] * 0.55 * 1.8,[人工价] * 0.55 * 1.8,IIF([后勤费基数] / [订单量] < [人工价] * 0.55 * 0.5,[人工价] *0.55 * 0.5,[后勤费基数] / [订单量]))