Hi @sdart101 –
All stats tracking systems collect and report information differently.
For example, Jetpack’s stats do not include visits from logged in users by default. Many site owners find this useful, since tracking your own visits artificially inflates your traffic. That might be one explanation for the variance between your other stats system and Jetpack’s.
Jetpack also does not report visits in real-time. That is, there’s a bit of a lag between when visits occur, and when they are reported in your stats.
Additionally, there are certain search engine robots and “spiders” that Jetpack doesn’t count, and referrers that are considered spam referrers by Akismet (our spam-catching plugin) will not be reported in your stats. Other tracking systems may be less discerning in what they count toward the stats they report to you, and therefore give you different numbers than we do.
Finally, the different rates at which all these trackers are blocked by the different ad-blocking browser extensions can also affect your stats.
For all of those reasons, different stat tracking methods will rarely, if ever, be in sync. You may find it worthwhile to use tracking data from a variety of stats systems to develop a broad picture of your visitors’ behavior.
When I browsed through your stats, it appears that you had more referrals in the 2nd to last week of December which seems to be accounting for the increase in traffic.
The Jetpack stats are tracked via the stats.wp.com JavaScript.
