And this surprises people, for what reason?
The only places were religion, particularly Christianity is growing, is in countries cut off from mass communication, freely available information and lower standards of education.
This is why RC, Mormons, JWs and such have always and recently have redoubled their missionary efforts in such places, to try in a desperate and ultimately futile attempt to off set rampant apostasy in the first world.
They are however face with a dilemma, in order to exploit the third world, they need those people to have access to more money, the only way to do that is to educate them, and as has been seen education leads to apostasy.
This is why we have seen in the last fifty years, churches investing heavily in corporate business, land and development, read for the inevitable collapse of all but a core church for each denomination, existing solely to funnel tax free money in to the church corporations and banks.