What determines whose power is Supreme?

[Panzerking]

Anyone know what the factors are for whose power is considered supreme? In a recent game I was supreme and yet was 3rd in the most powerful civ report!!
I think it has something to do with population, land-mass and cash but I am not certain. Anyone shed any light?
Cheers:

Panzerking

 

[TimTheEnchanter]

Your power ranking is reflective of your relative position on the power graph. All you need to know about where that ranking comes from is detailed in Andu's Power Graph Explained.

The one that shows up in a popup periodically between turns (someone wrote a book ranking everyone) uses a different formula.