I have noticed, that the gametracker chart showing the players for the day is not updating correctly. I had 12 players on my Jailbreak server yesterday, playing with me for almost a good 2 hours, and it only showed 6! Even though the player count on the website showed 12! Don't know why this is happening, but just wanted to let you know!

The historical data graphs show averages, not maximums. Each point represents an hour and an average of all of the scans over that hour. If you did not average as much as 12, it will not show twelve. It is safe for you to say you did not average 12 for a full two hours.