To je fair.
Everyone in the world has Rh factor.
Rh factor is either negative or positive. Positive is the most common while negative is a bit more rare. (Also, negative is dangerous for mother's because if they're child is to be positive, mother's will produce antidotes which might cause miscarriages).
It's unrelated to A, B, 0 system which talks about different antigens. So, possibility of having 0- is one of the rarest BUT it's normal for e.g. Indians or aborigines that probably have ONLY 0 type.