I found
this graphic that gives information on world population going back to about 100 000 years ago.
I don't know how reliable the information on it is, but I hope it helps.
Speaking personally, I find few things more awesome than contemplating this vast and majestic process of evolution, the ebb and flow of successive biotas through geological time. Creationists and others who cannot for ideological or religious reasons accept the fact of evolution miss out a great deal, and are left with a claustrophobic little universe in which nothing happens and nothing changes.
--
M. Alan Kazlev