Focus Gain Attribute

When I have The belt of superior focus equipped (30% focus gain), the corresponding attribute under character stats does not change. It's always at 0%  I'm not sure if the belt actually gives me improved focus gain and it's not showing up on my attribute page or if it's just bugged.  I didn't see any posts about it on this forum yet.  I've seen other reports of this on other message boards, but there's so much misinformation being tossed around...