The whole point of ssh-agent is to remember your passphrase. If you don't want to do that your problem might be that for some reason ssh client doesn't pick up your key. Try defining it for the host
Also, there's -v flag for ssh. Use it to debug what's going on when it doesn't try to use your key
The more I think about it, the less sense this graphic has
just checking on wikipedia, divided by area GB should have bar around twice high as Germany. 209k m^2 vs 357k m^2
big as a city sprawling datacenter complex and a bunch of racks in the cellar both count as 1?