The page describing the Site Analytics Privilege gives a bit of an overview:
Three graphs show a timeline of posts, votes, and traffic. Date selectors across the top of the page control the range of dates displayed:
Site milestone dates are also provided and, if clicked, will change the start date of the graphs. Selecting the "Weekly" checkbox will change the data points to per week.
Data series can be toggled via checkboxes to the left of each chart:
Get a CSV copy of the displayed data suitable for offline analysis by clicking the "csv" link. Note that unlike most other sources, such as SEDE, this data includes information on deleted posts.
This tab gives you access to select Google Analytics data from the last 30 days. There are a few oddities in the data:
- DuckDuckGo shows up as a referring site and not a search engine.
- The numbers are sampled so it's not uncommon to see implausible results such as several search engines at exactly 211 visits.
- We have a limited API quota, so arbitrary date ranges are not supported.
- Search terms are so unreliable that we just aren't showing them.
I can't really share any more information than that which is already available to the public (emphasis mine):
How should I use this data?
Since this is a restricted privilege, we'd prefer you not share the raw data. However, we do hope you will share your analysis of the data with other users on meta...
Please don't feel any obligation to share this data. (And if you don't yet have the privilege, please don't pressure those who have into sharing.) It's mostly intended as a way to satisfy your own curiosity about the state of the community.