I would say education more than wealth but both seem to be factors in fewer children. Maybe both those reasons result in more planning of families and the decis

I would say education more than wealth but both seem to be factors in fewer children. Maybe both those reasons result in more planning of families and the decision to not have 12 children. My dad's family had nine and he grew up in the city in a small house. I think religion may have some part in it for example Roman Catholic where contraception is frowned upon. It was quite common to have a dozen children. My mother's family who were farmers for awhile (then a restaurant) also has nine children. Government financial support may also play a role. My country Canada has many social support systems that allow larger family sizes. I'm not criticizing it but the support is there for the children. It would be curious to see family size versus government support.