I just realized how fucking stupid I really am. I mean I ride +21/+9. What an idiot! What happens if I end up backwards? Oh shit. Im really screwed now man. Lets change it now. For the love of God...These American standards are just shit.
0 is 0 degrees from perpendicular. Anything in the + range is pointing towards the tip, anything in the - points towards the tail. It makes it very easy to tell a persons stance angle whether they're goofy, regular, duck, forward, etc. etc. etc.