Dem, it is working, and this is how it calculates.
It is based upon a rolling 7 days or 168hrs
so if you post 1 post in 10 minutes where 167hrs, 59min 59secs ago you posted 5, your total will drop by 4
Do you understand it now?...its not based on a Monday to Monday thing, its rolling.
So if you were to post 10 posts a day, every day for a week your score would be 70. If you did not then post for the next 7 days, your score would drop by 10 per day down to nothing.
Posts are scored to the nearest second, so its incredibly accurate.