What percentage of phone calls (to your personal phone) do you answer?
I'd say I'm hovering around the 60% mark.
I don't answer calls from numbers I don't recognise, unless it identifies someone I'm expecting a call from with the "maybe" thing. I don't use my phone for work (often). I don't call people to catch up, I'd rather IM. My mother or my best friend call and I ignore them more often than I probably should.
But really I just don't like talking on the phone that much.
Basically none at this point. Unless it's recognized as coming from one of the handful of people in my address book, or occasionally if I'm expecting a call (like from a doctor or the mechanic or something). But otherwise there's no point. No one that would contact me or that I would want to contact me would use the phone - they would text, IM, email, etc. The odds of a phone call being junk or a scam is far too high to bother with.