We've had Google Analytics running against our Intranet for years now, and on the 12th August 2011 our number of Visits went down by a third and remains at the reduced figure daily. It transpired that a change was made to GA on the 11th (http://code.google.com/apis/analytics/community/gajs_changelog.html), one of those changes is regarding a session not being closed when users close their browser.
Given that everyone in our company has the Intranet site as their home page would this make sense? I'm very close to drawing a conclusion from this change, but I just wanted to see if it's feasible that this would cause this sort of drop?