NET EARNINGS IN DISTRICT I 337 
These and other relevant facts are graphically illustrated on 
Chart 50, which is constructed as follows: The vertical scale 
provides for the points change in ratios of gross earnings to earn- 
ing assets between 1924 and 1925, no-change being indicated by 
the space between the parallel horizontal lines, increases by the 
distances above, and decreases by those below these lines. The 
horizontal scale relates to the points change in ratios of total ex- 
pense to earning assets, no-change being shown by the space 
between the vertical parallel lines, increases by the distances to 
the left, and decreases by those to the right of these lines. These 
no-change areas divide the chart into four quarters or quadrants; 
the upper left-hand one represents increases in the ratios in both 
series; the upper right-hand one, increases in gross earnings and 
decreases in total expense ratios; the lower right-hand one, de- 
creases in both series; and the lower left-hand one, decreases in 
gross earnings and increases in total expense ratios. 
The dots on the surface of the chart indicate, for the 408 
member banks in the Boston district, (1) the amounts of change 
by tenths of a point in their gross earnings and total expense 
ratios, and (2) the points change in the ratios of net earnings. 
The diagonal zigzag lines running across the page enclose an 
area of no-change in net earnings ratios. The part of the chart 
above these lines is the area of increasing, and that below them 
the area of decreasing net earnings ratios between 1924 and 1925, 
the amounts of the increase or of the decrease for the respective 
banks being indicated by the horizontal distances between the 
zigzag lines and the several dots. 
With these facts in mind, the chart may be interpreted as 
follows: When gross earnings ratios are increasing and total ex- 
pense ratios are increasing or decreasing, an overwhelming pro- 
portion of the dots are above the zigzag line, thus indicating 
increasing net earnings ratios to be the rule. When total expense 
ratios are decreasing, while a majority of the dots are above this 
line—the banks thus having increasing net earnings—a consider- 
able proportion are below. It is these which had decreasing net 
earnings ratios. Moreover, this number is relatively larger than 
that falling below the no-change net earnings line for banks 
having increasing gross earnings. 
For banks with gross earnings ratios increasing and with total 
expense ratios decreasing—those in the upper right-hand quar-