As a finale we will finish up with a short flight into the realms of higher finance by asking the question that some of us may be faced with in the near future, i.e., what additional volume would be necessary to enable us to reduce selling price per unit and, at the same time, maintain or increase the return on investment? A square chart drawn from the foregoing standards taking the fixed and non-variable expense as a bar, and the material and labour cost as fixed wedges topped by the variable expense drawn between the two points of zero volume and capacity would practically answer this question out of hand.