The number of members, originally 196, is subject to change after each decennial census.
From 1850 to 1900 fairly full industrial statistics were gathered as a part of each decennial census.
But according to the eleventh census the decennial rate of growth of population fell suddenly from over 30%, which the figures had shown between 1870 and 1880, and in every preceding decade of the century, except that of the Civil War, to less than 25%, in spite of an immigration nearly double that of any preceding decade'.
The various departments of the federal and the provincial governments publish annual reports and frequent special reports, such as the decennial report on the census, from which a vast quantity of information may be obtained.
The first of the United States decennial censuses to show a decrease in the production of wrought iron was that in 1890, 35 years after the invention of the Bessemer process.