the information which is desirable from the standpoint of management. In order to show up the facts more clearly, curves "A" and "B" are plotted from the same data as curves "D" and "C" respectively. Curve "A" is plotted on a cumulative basis by the same general method used for Fig. 150 and Fig. 151. The total number of orders for the whole test period is first obtained, and then the cumulative number adding up to any class-limit line on the horizontal scale of the chart is plotted as a percentage of the total number of orders. Curve "A" joins the zero line at 200, showing that none of the orders was larger than 200 packages. We can see instantly that, because of the large number of small orders, only 22 per cent of all the orders handled were larger than twenty-five pieces per order. Only 13 per cent of all the orders handled exceeded fifty pieces per order. Also, by reading from the vertical scale opposite the figure for 50 per cent, we can see at once that only half of all the orders handled carried more than twelve packages.
In a manner similar to that used in making up curve "A", the cumulative curve "B" is made up from the data relating to the number of packages shown in curve "C". It may assist the reader to follow these charts if he keeps clearly in mind that curves "D" and "A" relate to the actual number of orders of various sizes, while curves "C" and "B" relate to the number of packages, or the amount of total business carried by orders of various sizes. In other words, curves "D" and "A" relate to the amount of clerical work needed, while curves "C" and "B" show the actual amount of freight-handling labor involved and measure the amount of revenue earned. Curve "B" thus shows that, though there are not many large orders, about 69 per cent of all the revenue comes from those orders which contain more than twenty-five packages. Fifty-six per cent of the business (and the revenue) is due to orders containing more than fifty packages. Twenty-nine per cent of all of the revenue comes from orders containing more than one hundred packages, yet none of the revenue for the ten-days time considered came from orders larger than two hundred packages, since there were no such orders during the period.
It is by reading curves "A" and "B" in conjunction with each other that the manager may obtain the greatest information relating to his business. Considering first the orders which contain more than ten pieces, curve "A" shows that 55 per cent of the orders contain more than ten packages, while curve "B" shows that 91 per cent of the reve-
