It would then be simple to compute the income of each group as a percentage of the combined income for all groups. The resulting group percentages would be plotted cumulatively as the dependent variable on a chart for which percentages of population would be the independent variable. Fig. 161 unfortunately shows the independent variable used for the vertical scale. A better arrangement may be seen by observing the illustration through the back of the paper with the two zeros appearing at the lower left-hand corner.

GRAPHIC METHODS

Diagrams made on the scheme of Fig. 161 are of very great assistance in studying such matters as the distribution of ^^ealth for any country. The subject of weahh distribution is so complex that unless data are expressed graphically there would be very serious difficulty in getting a true understanding and appreciation of the different factors involved. In Fig. 161 we have the curves for two widely separated years plotted side by side, so that we may tell from the general shape of the curves whether the distribution of wealth is approaching uniformity of tending in the direction of great concentration in the hands of a few people. The more nearly the curve approaches a straight line the more nearly wealth is distributed uniformly among all the

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