Just a quick little thought that came to me.

Instead of having to do the calculations yourself,
maybe the website could calculate your qi per day, kinda like posts per day.
This could help with finding out if someone is active ingame.
I'm not sure where it would go, but I think it would be helpful anyways.
Probably near the "posts per day" in your user profile.

...Or is this already in the forums somewhere? >.<

Extra crap:
How I found mine: (Total Qi)ї((Total posts)ї(Posts per day))
How the website could: (Total Qi)ї(Days since join date)