Welcome to WebmasterWorld Guest from 188.8.131.52
By default, we'll show the last 30 days of data, along with how the daily average for the selected period compares with the daily average for the previous period.
That doesn't tell us exactly what happens after we change the reporting period to something other than the default. I've always assumed that a period of N days, the change was figured over the preceding N days - but I can't find any documentation for that.
Thanks for the detailed reply aakk999. So if I do the last week you think it is comparing to the week before?
And if I do March 3rd and 4th it is comparing them to the 1st and second?
but when I look at my numbers the don't always make sense to what my actual traffic and referrals have been. Webmaster tools will often show big ranking drops or increases across the board when the reality is my traffic has been pretty stable, except for day of the week traffic patterns, for 3 weeks straight.