I have not seen your post, but I recently made some research into the population of North American nations around the year 1910 and I compared them to each other.
While I have occasionally posted bits and pieces of my work on CS population numbers (mostly on FILLING THE GAPS), my complete numbers for the CS population between 1865 and 1935 have never been posted in full on Alternate History.com - mostly because there are quite a lot of them and statistics alone make dry reading, but also because I was never completely satisfied with my post-Great War population figures (mostly because I could never be quite certain how to factor in casualties from that conflict).
It might amuse you to know that I actually started the mini-project in question so that one could work out the proper apportionment for CS congressional delegations, but found myself being pulled farther and farther down the rabbit hole - statistics are an absolute nightmare to keep straight but can be bizarrely addictive!
*I lowered the population of Maine because some of its northern part was taken by the British in 1882.
**Alaska and Hawaii are not included since it does not belong to the USA in TL-191.
I was not only unable to work out how to properly allow for the diminution of Maine, but also completely forgot to subtract Hawaii & Alaska - so please do be aware that I'm a rank amateur when it comes to this statistics lark!
*In real-life, the population of Oklahoma was more than one-and-a-half million. I lowered it to 500,000 to account for a nearly pure Native American demographic.
Ditto! I actually came out with a figure of 322,370 (although I can't remember how one arrived at this figure - possibly by taking the population of the Indian Territory before the "Sooners" showed up as a basis).
***In real-life, the population of African-Americans in the U.S. was 9,827,763. Most of that population would be located within the Confederacy and the total Confederate population eligible for military service would be more small (18,284,632 Whites within the CSA; an estimated half would be 9,142,316 men).
Wikipedia, our friend and help in all researches, actually has a whole page on African American demographics by State; as you might imagine, I drew on this rather liberally when drawing up each Census of the Confederate States of America!
https://en.wikipedia.org/wiki/List_of_U.S._states_and_territories_by_African-American_population
^^ Please remember that I originally drew up this Census to help me work out the precise size of the delegation from each CS state to their House of Representatives and since the Confederate Constitution requires that each person of colour be counted as 3/5th of a person - please picture me spitting in distaste at this point - it was quite important to have a reasonable idea of what proportion of each states population would fall under this unpleasant little rule. ^^
My sources are from the Demographics pages from each respective country on Wikipedia. The citations are an interesting read.
I may have to go back and look at those citations, but I most definitely relied on Wikipedia almost exclusively when drawing up this Census - the only exception was in the case of Cuba, where I was lucky enough to stumble across a website with a somewhat more detailed breakdown of the Islands population.
http://www.populstat.info/Americas/cubac.htm
^^ You can find that website here - see what I mean about it being a godsend? ^^
I also remember fiddling a bit with the population numbers for Sonora & Chihuahua; being a natural born masochist, I just HAD to draw up every Confederate census between 1865 & 1935* so I estimated the population of Sonora & Chihuahua in 1885 by subtracting a percentage of the population roughly equal to its growth between 1895 & 1900 and used that as the "base figure" from which I might model population increase.
*With the logical exception of 1915, when the Confederate government would have been a TAD busy; the Sixth Confederate census would have to be held after the Great War (one assumed in 1919, in time for the tertiary Congressional elections in that year), quite might have been postponed until as late as 1925 if the Whigs really wanted to fudge things in their own favour.
I have not seen your post, but I recently made some research into the population of North American nations around the year 1910 and I compared them to each other.
My advice for modelling the population growth between 1910 & 1914 would be to take the population increase between 1910 & 1920 (the total number, not the percentage) divide that number by 10 and then multiply the resulting number by four; applying this to the (undivided) United States suggests a population of 97,745,712 in 1914.
For the record my method when working out the Confederate population increase was to take the pre-Civil War population figures and average out the percentage increase for each state between (say) 1870 & 1880, then apply that percentage to the population of that state; as you might imagine, this involved quite a bit of fiddling around and "best guess" work but it was still a reasonably pleasant diversion.
For the record, my own estimates for the Confederate population in 1914 indicate a total population of 32,119,222 - of which 22,075,942 White (or "White enough" allowing for Confederate attitudes to First Nations, Hispanic & creole populations) and 10,043,280 Black (or "Too Black" given that ugly, ugly 'mudsill' theory); I derived a rough estimate of military manpower from this population by estimating the percentage of the French population that was mobilised during WWI and applying that figure to the Confederate population (deducting Confederate coloureds from that number according to the percentage of the total CSA population they represented).
This left me with the figure of 6,240,702 White (or "White Enough") Confederates mobilised for the defence of the South (and I then proceeded to divide this number up by state, according to the percentage of the total population that state represented).
Did I mention that statistics can be quite, quite addictive? I really should have because you fellows really need to learn from my example & take warning!