Take a read of this thread first:https://bitcointalk.org/index.php?topic=1689727.0

More specifically:
How is forum activity calculated?
Activity is calculated with the following formula:
Code:
activity = min(time * 14, posts)

Activity is increased by staying logged in or by posting and is updated every 30 minutes. There is a maximum of 14 activity points every 2 weeks.
We would like to credit everyone who has been linked inside this thread. Thanks a lot for the hard work. If you see any mistakes or have a suggestion, please message me or Mitchell and we will look into it.