The mainline is trouble because you need kids to keep things going and they don& #39;t have that.

The denoms appearing at the bottom of this graph are largely mainline (ECUSA, ELCA, PCUSA, UMC).

The groups at the top are largely evangelical(AoG, SBC, CofC, Pentecostals, Non-denoms)

And here& #39;s a scatterplot of how education interacts with having young children.

There& #39;s a slight negative correlation that& #39;s statistically significant. A 1% increase in college degrees leads to .18% fewer parents of young children.

And, really, at the end of the day this is more about age than fertility. It& #39;s hard to have kids in your congregation when the average age of your flock is 58 years old.

Note that 5 of the 6 oldest denominations are mainline here.