Denominational fecundity, conversion, and apostasy

I read today that:

The conservative denominations have grown more than the mainline denominations in large part because they have higher fertility, and that has given them a growth advantage. But part of conservative growth is attributable to the recent decrease in conservatives' rate of switching to mainline denominations. While the diminished influx has hurt the mainline denominations, it has not necessarily helped the conservative ones. That is because conservative denominations are losing the same fraction of their young people as they were losing 30-50 years ago; intergenerational persistence has not increased for conservative denominations. People leaving conservative denominations have just changed their destination after a switch. Conservatives used to switch to mainline denominations; recently they have chosen other religions (especially Catholicism but also some of the "other" religions) and no religion more often than they have chosen the mainline denominations.

-Michael Hout; Andrew Greeley; Melissa J. Wilde