The only things that are innacurate in the post stats graph are the following:

-All stats since April 23rd 2012 are 1 day off. To fix this just INSERT INTO `currentdbname_log_activity` VALUES ('2012-04-23', 0, 0, 0, 0, 0); or whatever you have to use to manually add stuff in the database. Another fix solution is to make the graph scan dates and count any missing day/stats as 0 posts.

-From May 2005 to March 2008, stats excludes deleted posts, while newer stuff includes them. I think it's OK as it is, though, since almost every deleted posts from the old board were parts of the old downloads section anyway, with only 1 accidental topic deletion and 2 or 3 dispute deletion in 2006.

-The timezone changed 3 times through the stats. GMT+7 until Jan 1st 2008 (Invisionfree glitch), GMT-5 (Zetaboards & resurrected Omni), GMT+1 (since 2012 server move)

EDIT Wow I like the other graphs above the main one

How much will changing the time zone affect the stats?
The top graphs are nice, though quite condensed, I wonder if the range could be chosen to view previous years' stats.

I haven't coded in the ability to choose between certain times yet into the stats API. Currently it will only look back 30 days. I'll add in some better selection soon though. I'll also work on making them a bit wider.