The Daily Activity report details the traffic history of the site, logging hits and visits for each day. Please note the following caveats when interpreting this data:

• Hits--every request, whether for an image or a page counts as a hit. One page with five pictures would generate six hits for each visit with a graphical browser. It is very important to remember that Hits != Visitors.
• Visits--it is impossible to completely sure of the actual number of visitors you have each day, due to proxies, varying cookie support in browsers, etc., so we have to use a few assumptions. The assumptions we make here is that any visitor to the site will typically take less than 30 minutes to read each page. If another request comes in after that interval passes from the last hit, this is probably another visit. Because proxies allow users to browse simultaneously, this number tends to be a bit conservative in most cases, making the actual count higher.