Since November 2nd the total daily visits to one of our websites have halved.
This is from all traffic sources(direct, organic and Paid), which rules out a drop in rankings (plus rankings are virtually the same).
Another peculiar thing is that it only seems to be the Homepage which has lost page views. All the other pages of the website have actually seen more page views since the said date.
The drop seems to be across all countries and cities, as well as key terms (including - "Not Provided" and Brand Name terms)
I have checked webmaster tools and all is in order, a few pages not found but nothing critical. The robots.txt file seems to be all in order as does the tracking code itself.
If anybody has any answers, or suggestions of things to check, it would be much appreciated.