If you discovered about half of the students in your church's youth ministry were going to walk away from Christ after entering college, would you do something about it?  I hope so.  That's not a very good retention rate. 

But what percentage of Christian youth are actually leaving the church?  There’s been some debate about the actual number, with some saying as little as 4% will remain Christian, while others suggest there’s virtually no exodus.  Christian Smith tells us that evangelicals have been "behaving badly with statistics" and quickly dispenses with the 4% "panic-attack" stats.   But can we get some idea of the percentage of youth leaving the church without being irresponsible with numbers?