A question for the Brits...?

I'm an American but I studied in England for a year. My religion professor there said 80-85% of Americans describe themselves as religious, while on 35-40% of Britions do. I was told by many there that fundamentalists are practically non-existent there, and those who are there are considered very fringe. But I never got the sense that there were radical atheists either. People tended to be personal about it, so I don't know if they were quiet atheists, agnostics, Deists or even non-religious Christians (people who believe in God and Jesus but don't attend church or pray in public)