I remember reading an article on birth rate differentials between France and the US during this period. What it boiled down to was this. French parents had less children during this time period because the economy tended to be more stagnant than in the US. They were therefore more concerned with having to support extra children in an economy where there was no way of knowing if all their children would find jobs, and how many they might need to support otherwise. Simply put, even before effective birth control the French were, compared to Americans, engaging in 'family planning' for reasons of economic self-interest.
As to how to model this in the game, I think the easy answer would be a 'growing economy modifier' for population growth. Of course, this kind of presumes that there will be some form of economic growth in Vicky besides pop growth/events/tech (unlike in EU2). We would need more information on economic development to know I think.
As to how to model this in the game, I think the easy answer would be a 'growing economy modifier' for population growth. Of course, this kind of presumes that there will be some form of economic growth in Vicky besides pop growth/events/tech (unlike in EU2). We would need more information on economic development to know I think.