CURVES FOR THE EXECUTIVE 267

difficult with a loose-leaf book to arrange a system for keeping hundreds of curves in such a way that quick comparisons between any of them can be made. When loose cards are used any card can be compared with any other card instantly, and, if desired, cards for any curve for a series of years may be laid out for comparison with cards for any other curve for any series of years. Anyone without experience in the analysis of curve records for large corporations may take it as a fact that no system of curve records should be installed which does not permit the instantaneous comparison of any curve with any other curve in the whole system.

Fig. 207 and Fig. 208 show the shipments from an automobile manufacturing plant as sales. Many of the automobiles recorded as sold were shipped to branch houses owned by the same company, to be stored there during the winter months when the branch-house sales are very small, for the reason that people do not wish to buy touring cars in winter. In Fig. 209 and 210 more curve records from an automobile business are given. In these cuts also, as in Fig. 207 and 208, cards are shown in groups of three, photographed against a black background. In Fig. 209 we have in the upper curve the actual sales of an automobile branch house selling direct to the automobile user. Notice that the sales in the spring months greatly exceed the sales at any other time of the year. In the first two fiscal years sales were at a maximum in May, while in the third fiscal year sales reached the maximum in April and were fairly large in both March and May.