6

In my early teens. I think it was my first year of high school.

My faith started deteriorating while I was in my 20s. I continued to play the part up through my early 60s, because it allowed me to maintain credibility in discussions and arguments. I really abandoned christianity around age 64.

Looks like an average of sixteen years of age so far.

Always had a degree of skepticism. Never believed in Santa clause or any other BS assertion so when I was around 9 I noticed the church was preaching things that were definitively not representative of reality, I figured religion (church) was nothing more then another (Santa Clause) story old people used to try to control ignorant children.

I did not realize many old people never grew out of accepting faith based superstition (belief without evidence over testable reality) until I was about 20. That was a sad realization. That day my optimism for a global better outcome was greatly diminished.