What's the rarest blood type?

blood type Blood groups in Australia · O positive - 40% · O negative - 9% · A positive - 31% · A negative - 7% · B positive - 8% · B negative - 2% · AB positive

ABO blood group system, classification of human blood as determined by the presence or absence of A and B antigens on red blood cells  blood group Blood groups in Australia · O positive - 40% · O negative - 9% · A positive - 31% · A negative - 7% · B positive - 8% · B negative - 2% · AB positive