I haven't touched refrigeration in a long time and need some quick help.

Basically i have 1800HP of compressors at a facility.
1 -400HP Screw
1 -125HP Screw
2 -600HP Screw
1 -75HP booster
1 -100HP reciprocating

Looking on the HMI screen of one of the screws, it shows the following:
Cap: 98%
Pos Valv:54%
% Vol: 47%

It's running ammonia (R717)

How do I find the percentage the compressor is loaded at?
I should know this, but I haven't touched on it in a few years and quite honestly I don't want to go back to my text books. I know there aren't dumb questions, just dumb people. Guess I fall into the latter.