A while back I commented about the moving population center of mass of the USA. One of the questions we wondered about was why there was such a small jump in the period from 1910 to 1920. Perhaps some more insight can be gained by a new widget released by the Census dept. It allows you to click on a decade and see the changes from census to census and over time... The mouse over features take a little time to fully appreciate.. they show figures for each state and adjust the population timeline on the left to show that state. Seperate tabs show population density and legislative apportionment for the states as well.
Lots of information to process.
As far as the period 1910 to 1920... it seems that the west was still growing rapidly, as was the east, but compared to 1900-1910 when may western states had gained near, or over, 100% population growth; in the 1910-1920 period many slowed to a growth of 50-75%. Decreases in growth in the east occurred also, but were not as great as the differences in the west. From 1910-1920 there were actually three states that lost population.
Another interesting census to look at is in the 1940 census... look at the loss of the five states in the heart of the dustbowl....In fact, the 2011 census was the first time that North Dakota has shown growth in two consecutive census reports since 1930. Their total population change over the 60 years is almost zero.
see the actual one here.