Page:Graphic methods for presenting facts (1914).djvu/190

 compare the two illustrations to see just how much more clear Fig. 145 is than Fig. 144.

The bottom portion of Fig. 144 is shown here by way of contrast with the upper portion. Notice, for instance, the difference in the shape of the chart for the female Chinese and Japanese population of the United States as compared with the chart for females in the aggregate population of the United States. A very large percentage of female Japanese and Chinese are married by the age of thirty-five, but after that age there is a fairly large percentage reported as single. It would appear that many widows must be reporting themselves as single instead of as widows, or the chart would probably not be so different in shape from the chart for the aggregate population of the United States.

In Fig. 145 the scale for age has been properly placed horizontally and the scale for percentage placed vertically. The whole population is considered as single under the age of fifteen. The total of the figures for single, married, and widowed on any vertical line equals 100 per cent; thus, as the number married in succeeding years increases, the number who are single is seen to decrease. The curves prove at a glance that the women start to marry much earlier than the men. Between twenty and thirty-five the horizontal difference between the two curves shows that the women marry about four years earlier than the men, or, in other words, taking the population as a whole, the women marry men about four years their seniors. In considering these curves it must be remembered that this chart is made up on a different basis from Fig. 143. In Fig. 143 all the women who married are recorded as married, and the top of the curve (the mode) shows at once the age at which marriages are most frequent. In this chart, however, we are considering three things, and the chart shows the percentage who recorded themselves as married, rather than the actual age at which marriage occurred. The percentage of those who report themselves married is affected by the number who are single and also by the number who are widowed. If in the later age classes, deaths of husbands occur more rapidly than marriages of spinsters for any particular age, the "married" curve will trend downward even though a very large number of spinsters may be marrying at that age. It is simply a question of balancing the death rate of husbands against the marriage rate of spinsters. The curve marked "married" on this chart does not show the age at marriage, but simply shows the percentage in any age class who report themselves as married and not widowed.