\mbox{COGS}_i = \mbox{q}_{L,i}^{\uparrow} \cdot \mbox{COST/qL} + \mbox{q}_{O,i}^{\uparrow} \cdot \mbox{COST/qO}+ \mbox{q}_{G,i}^{\uparrow} \cdot \mbox{COST/qG} + \mbox{q}_{W,i}^{\uparrow} \cdot \mbox{COST/qW} + \mbox{q}_{WI,i}^{\downarrow} \cdot \mbox{COST/qWI} |