None of this is really surprising. Historically, most faithful church members are middle age and above. Younger people have never, by and large, been active in church life. As people come to the point in their lives where they have fewer tomorrows and more yesterdays, their minds turn towards eternity.
What is interesting, at least to me, is the fact that so many churches expend enormous resources in attempting to woo young people to faith when, in fact, time will do that all by itself. It always has. It always will.