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the years selected as unity should be taken in equal number on either side of a year which represents most nearly the normal condition.

Courtesy of F. J. Warne, Washington, D. C.

Fig. 95. Relative Retail Prices of Fifteen Principal Articles of Food in the United States, 1890 to 1912, by Simple Averages and by Weighted Averages. Average Prices for the Years 1890 to 1899, Inclusive, Were Taken as 100 Per Cent

The solid line shows ordinary averages of the prices for each year considered. In order to get the data for the dotted line, estimates were carefully made of the average consumption in workingmen's families of each of the fifteen various articles of food. The food prices were then "weighted" in proportion to the quantities of each kind actually consumed and the averages shown by the dotted line were obtained. The prices of foods to the workmen did not increase as much as the simple averages shown by the solid line would indicate

Fig. 95 is an illustration reduced in size from a large chart 10 by 14 inches. The chart is of especial interest because it is one of a series of several hundred charts submitted to the board of arbitration in the concerted wage movement in the eastern territory by the Order of Railroad Conductors and Brotherhood of Railroad Trainmen in 1913. These charts cover practically all phases of railroad operation and give in condensed form a tremendous quantity of information. There is such a great quantity of data arranged in convenient form for reference, it seems likely that a person wishing to study railroad operation could obtain more insight into present-day railroad conditions by two-hours' study of this series of charts than he could pos-