Post count within a date range

[Doc203]

On our board we give a prize away every month for the person with the most posts that month.

Right now I go into the database and manually extract the post counts and do the math. I would like to have a hack that would do that for me, and maybe even show under each users profile the number of posts they have so far each month. Then lastly I would like to have a seperate "stats" page that you could see who the top posters were every month for the past however many.

Thanks for any help!