activity the same

It's because the current week is full. You will have to wait for missed opportunities in the past to pass. Here is your info:
4v,4v,4v,4v,4v,4v,4v
4v,4v,3v,0v,4v,4v,4v
4v,0n,4v,4v,4v,4v,4v
4v,4v,4v,4v,4v,4v,4v
What this means is:
This week, you have visted 7 times, and posted 4 times each day. (7*3+(4*7)*2)*36 = 2772/2772 for this week.
Last week, you visited 6 times, and posted 4 times each day that you visted (24 posts total). (6*3+(4*6+0*1)*2)*27 = 1782/2079 for last week.
The week before, you visted 7 times, posted 4 times 5 days, and 3 times one day. (7*3+(4*5+3*1+0*1)*2)*21 = 1407/1617
Three weeks ago, you visited 7 times, and posted 4 times each day. (7*3+(4*7)*2)*16) = 1232/1232

Total: 7193/7700 = 93.415584415584%

Basicly, once you're obtaining 100% activity for each day, your percentage increases when passed missed oportunity changes number of weeks ago. If you continue your current trend, you should be at 94% in 4 days; a week after that, 97%.