The majority of the userbase is, per the green color of the usernames of most users on the members list.
Oh I know what you're talking about now. You see, even though Retired Staff is a separate member class, they have the same color of username as regular members. Weirdly enough, the key doesn't specify the color for regular members though so it looks like every one that isn't a part of staff is part of the Retired Staff group even though they're not. You can always see what group someone is in though by going to their profile/a post of theirs and look one line down from their username. If you're a regular member, it will just show what your posting rank is. If they're in a group as well though it will say before the posting rank.
Honestly though, Retired Staff and regular members are the only ones who share the same username color.
