I could be using cookies for login to the city sites, but it shouldn't be any different than the main site (citydogmagazine.com) that has a Cache Hit Rate of 88.1%.
So, just to be clear, the minimum cache age, "No Restrictions" should be set to 0?
And the rest of the Advanced Settings:
Enable Caching For Cookies OFF
Default Cache Age (s) 7777600 seconds (90 days)
Maximum Cache Age (s) 3600 seconds
Minimum Cache Age Threshold (s) 300 seconds
Minimum Cache Age (s)
Override Cache Control Headers ON
Force Caching by Device Type ON
Vary Headers to be removed from origin
Grace Period 600 seconds
Vary Headers to be added to origin
Allowed HTTP Status Codes 200 301 302
Thanks for your help.