My first thought was that the stats on the admin page are just for the last 100 days, but there is no indication this is the case. Or is the “Flags Given / Received” some specific metric that is not obvious?
I found this post about accessing a user’s admin page, but I couldn’t find a page that explained in more detail what was happening with these numbers.
My thoughts are that out of 20 flags a user has given, only 14 were found helpful by a moderator (they agreed to the flag). And from the 73 flags that user has received, a moderator only agreed with 23 of them.
From what I see in the code, it seems to be all the flags that auto-hide content, meaning the flags without required messages: offtopic, inappropriate, and spam flags.