Racial HD Reference in Pathfinder

I'm working on my Dragon Mount, which has a Breath weapon. The DC for the Breath weapon is based on the Racial HD of the Dragon. However in creating the Macro I was unable to find what @{XXX} references this number. Can anyone tell me what it is? I wasn't able to find it on the Character Sheet page (<a href="https://wiki.roll20.net/Pathfinder_Character_Sheet" rel="nofollow">https://wiki.roll20.net/Pathfinder_Character_Sheet</a>) either.

If you are using the Pathfinder and not "simple" sheer then On the sheet for your mount, go to the class gird and.check "add racial HD" and you'll see it appear. It is @{npc-hd}&nbsp; If it has no class levels then you can also just use @{level} which is easiest&nbsp;