I finished the spreadsheet and updated my original post. The data inside the dotted box is estimated; I didn't sum the posts of all those users, but the bottom line should be accurate within two percent.
Random Findings:
1. Registered users have made ~75% of the posts on the forum.
2. Guests have made the other 25%.
3. The top 14 registered users (with more than 1500 posts each) account for over 25% of the forums' posts... more than all Guests combined.
4. The bottom 92% of registered users (with less than 20 posts each) account for only 11% of the forums' posts... less than the top 4 posters have.
5. More than a third of the users who have registered have never posted, yet the forum has over 20 posts per user on average.

BoBo has made approximately 1.85% of all posts on the forum, and 7.25% of all Guest posts.
Historical context:
Nearing 6000 users!