After this first chart has been made, a second chart can be drawn in which the "Price" cvu've would be plotted exactly as in the first chart. The curve for the number of barrels of "Exports" should, however, be plotted downward from the top of the chart, after a good position has been selected for the top of the chart so that the "Exports" curve plotted downward from the top would coincide as nearly as possible with the "Price" curve plotted upward from the bottom. The scales for the

COMPARISON OF CURVES

curves in the second chart should be the same as those for the first chart, so that there may be no "faking" in any similarity which may show up in the shapes of the two curves. It frequently happens that the relations between two curves are such that the most striking presentation can be obtained by plotting one curve upside down so as to bring the two curves as closely into coincidence as possible, and the scheme should be kept in mind as it is frequently of assistance in making facts stand out vividly.

CoiiTlcsy of Penn.il/tvanta Farmer

Fig. 117. Exports of Apples from the United States as Compared with the Average Wholesale Price in the United States

A little inspection shows that the export curve usually goes up when the price curve comes down. Though this fact indicates an inverse relation between the two curves under consideration it does not give satisfactory proof that exports fluctuate relatively as much as price.