Apparently, this bug is caused by the game saving the data in the wrong address (I'm not a programer so I might be wrong) but what is shown in your screen isn't random so there is a specific setting for every option there:

1. Server Tick Rate ---> Client FPS
2. Idle Time ---> Frame Time
3. Packet Loss (Total) ---> PING
4. Packet Loss ---> Packet Loss (Total)
5. Whatever you set for the Bold ones, will be shown as italic ones (eg. Show graph for Idle Time, Graph for Frame Time will be shown after rebooting) and will be saved like this unless you open the Stats settings.

These are the most used ones and I don't know about the other options. Hope they fix it soon.