This report, portions of which were published as monographs in bulletin form, is in the nature of an analysis and interpretation of statistics contained in the main reports of the Twelfth Census—particularly of the statistics of population.

The derivative tables in the latter half of the volume include many which are not discussed in the text. It is believed that they carry their meaning on their face. Many of them indicate statistical differences between city and country—a basis of classification which, for many purposes, is more significant than the usual one between states and counties. A large number of ratio tables have also been introduced.