Or you can just make a chart or somthing to tell what percentage of post the user did in which board. This would effectivily tell the potential buyer if he wants to buy the account or not ... Moreover you can really easily pick this up from the user profile.
You can pretty much get this chart from your profile's general statistics page =>
https://bitcointalk.org/index.php?action=profile;u=167251;sa=statPanelSo that isn't much important either.
That and the site already tells you where they have posted and how many times they posted in each section.
@knightdk, I would rather suggest you to add a negative multiplier or a lower positive multiplier for posts in off-topic, politics and altcoin sections.
I will add that. There will be an additional positive multiplier (e.g. price*0.7) for those sections. Can you suggest me some multipliers to use?