Use the sarg-reports command to generate reports as shown below.
# to generate the report for today
# on daily basis
# on weekly basis
# on monthly basis
Note: Add the sarg-report to the cronta
The reports generated by sarg are stored under /var/www/squid-reports. These are html reports can you can view from a browser.
$ ls /var/www/squid-reports
$ ls /var/www/squid-reports/Daily
2010Aug28-2010Aug28 images index.html