It displays Current available Rep points / Lifetime earned Rep points. Once you have earned 600 total rep points for a particular faction in your career (for that character) you will be Trusted with said faction regardless of how much you spend.

Edit: And, yes, this has been explained multiple times in this thread but it seems as though the op is not understanding so I added my variation of the explanation hoping perhaps when worded differently it would make it click for him/her.