for exports to decrease as prices increase, there would seem to be so many complex factors entering into the relation that no very general law of dependence can be proved.
It can be seen from inspection that the relations existing between the two curves of Fig. 118 are much closer than exist between the two curves of Fig. 117. It is unfortunate that in Fig. 118, as well as in Fig. 117, the chart was carelessly prepared so that the two curves do not have the same zero line.
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Courtesy of Pennsylvania Farmer
Fig. 118. The Average Price of Apples in the United States as Compared with the Total Supply
Here again an inverse relation is indicated, but the chart has carelessly been made with the two vertical
scales starting from separate zero lines so as to cause distrust by the reader. The chart is printed showing
a finely ruled co-ordinate background, though only every tenth line is desirable for the reader. The
use of more lines than necessary should be avoided as it tends to cause confusion. See Fig. 119 as
another method of charting the same data
In order to determine just how closely the price of apples depends upon the supply, Fig. 119 was prepared from the data of Fig. 118. Though the dots in Fig. 119 represent a rather long series of years, they nevertheless have a fairly symmetrical arrangement and the general tendency might be approximated by a smooth curve drawn as shown. It must be remembered that there are many conditions which may affect the position of these dots on the chart. For one thing,
