Nine in 16 years, from only 3 different posters.
Total of two in the last almost 18 years.
So rarely that half the time I wind up not noticing them in a timely fashion. Nine received, four sent in the profile record, probably half as many previously cleared.
Rarely, maybe once or twice a year. I don’t use it really, but am glad there is such a feature.
Basically only when I’m doing an exchange.
I’ve had a handful of others for various reasons, but it’s mostly the exchanges.
Don’t think I’ve ever gotten any.
80 in six years.
Every so often. A few from Idle that I enjoyed.
125 in 16 years. Some of them from Idle, which I enjoy. Even if I don’t respond.
ETA: I will say, I was a little hurt I didn’t get the “I’m really a girl” PM. 
In almost 17 years: About one warning a year in the last five years for Being A Jerk (must be age). A few less-than-warnings or other heads-ups from mods. The odd inquiry about something I posted. Largest category would be PMs I solicited for some reason.
Maybe 100-120, all in?
I have three of them this year, all of them from Idle Thoughts, two related to a contest I won because of my lack of posts in Great Debates. I won $10!! I told I_T to buy a lottery ticket and we would split the proceeds. (never heard back).
I don’t get very many and that’s OK.
Proud to say that I never got a warning or even a PSSST, you are being jerk from a Moderator.
Yeah me!
I’ve gotten a few, including one from you (Idle Thoughts) that I just saw again before responding to this, and it was from a thread you started asking about a strange beeping noise or something in your room. It’s been bugging me for a while, did you ever figure it out? (thread was from 2 years ago, not sure why I started thinking about it recently)
Coming up on 17 years on the boards, I have 8 PM’s - 4 received and 4 sent. I like to keep it balanced, ya know.
I get one every few months, and tend to send one out (generally because someone said something awesome) maybe once a month.
I didn’t get any from 2001 to 2008. From 2008 to 2012 I averaged 2 or 3 per year. In 2012 I became a mod, and I’ve received about 400 since then. Very few of those were non-mod related.
153 since 2007.
Very rarely. I’ve had 25 in the last 16 years.
I have yet to delete a PM.
Join Date = July 2000
Total PMs = 9
So, about once every 1.8 years.
Oops, the PMs are 2 sent, 7 recieved.
So, I receive one about once every 2.4 years.
Five or six a year although with a couple of the threads/tasks not continuing (Christmas Cards for Doper Kids for example) it may be way less in the future.