White Balance RGB, RGGB etc Levels

[blue-j]

There are a number of fields that are labeled White Balance - RGGB Levels, for example.  But the values aren't clear to me, they don't appear to be in any obvious bit depth.  Can anyone point me to an understanding of what these values are and mean?  Thanks in advance.

- J

[Phil Harvey]

The ratio of these values is important, but the absolute values vary from model to model.

- Phil