Population loss after creating a vassal

[German Conqueror 9]

This has been bugging me for a while. Why does the population of a new vassal decrease a bit when right away it was created? Is it a glitch or a bug? Or is it an intended feature? Never really understood it either.

[UCH 2]

I dont know but it probably has something to do with conscription, all nations in the start of the game instantly recruit an army, also if you release a vassal in a region that has lots of your original population, your vassal will have to assimilate its land so all the population that was yours can become theirs, sorry if this reply was a little bit confusing