With Fig. 249 as it is, the 1908 bar shows a great increase over 1907 and the reader is quite justified in wondering how it happened that a greatly increased number of telephones were installed during a panic year. From the chart as shown the reader is not likely to realize that 1908 is getting credit for the telephones installed during 1907, which happened to be a very prosperous business year. Having the data recorded as of December 31 each year overcomes the difficulty and makes certain that no false impression can be obtained.

Fig. 250 shows the data of Fig. 249 plotted as a smooth curve. For a trained class of readers the curve presentation is preferable to the bar presentation, for it permits seeing the fluctuations which have occurred from year to year more easily than they can be seen by glancing from bar to bar in Fig. 249. Within a few years it is probable that curves will be so well understood that a report to stockholders could best be made using the method of Fig. 250 instead of the method of Fig. 249.

In order to show the different impressions which may be had if various proportions between the horizontal and vertical scales are used, Fig. 251 has been plotted from the same data as Fig. 249 and Fig. 250. For Fig. 251 an assumption was made that the chart would be printed on exactly the same size page as was used for Fig. 249. The scales for Fig. 250 were, however, arranged in the other direction on the page and the co-ordinate ruling was made so that some space would be allowed for extension of the curve in future years. As seen from Fig. 251 the growth in the telephone business does not appear nearly so rapid as would be thought from observing Fig. 250.