ask about source and method
I came away with two things: 1) the number of unbelievers is indeed growing and 2) comparative statistics don't mean anything unless the methodology by which they were created is objective and consistant. This brings to mind a story I've heard from a administrative assistant for a statewide organization whose representatives were sometimes called on to speak before local civic groups. After typing up a speech for one - this admin asked where his statistics came from. "Oh I just make them up - people don't question...." he said adding he'd never been challenged. The lesson is when someone, even someone who should know, rattles off statistics: ask about their source and its method. People are free to say whatever they like - that does't make it true.
Thanks to Tom Flynn and to HAC for the opportunity to hear him speak. Flynn is author of a number of books, among them a debunking of modern Christmas traditions called The Trouble with Christmas and two science fiction sagas: Nothing Sacred and Galatic Rapture. He is also editor of the New Encyclopedia of Unbelief.