Since I normally participate mostly by responding to emails from topics and boards where I am subscribed, I get LOTS of individual, short sessions where I don't post. So, my percentage of participation might actually be low. Also, when the board changed, the criteria for full participation went from an average of 3 posts per day to 5 posts per day. I wasn't able to participate for some time then, and with the combined effects, my participation went from the high 80s and 90s to the 40s.
With all the time I have been here, it is hard to raise this percentage very much - so, my percentage isn't a very good indicator of how much I participate.