Squid Graph is a free, simple, yet powerful Squid v2 native logfile analysis tool that generates reports with graphical representation of the proxy server's traffic, somewhat like the popular MRTG tool.
Open source project that offer summary and download services on this page is a project that carry out their development work on other open source development sites. Their work is linked to this page via a feature called OFI, and their work is not carried out here on OSDN site.