Human Blood: Table of ABO and Rh Blood Type Frequencies in the United States

ABO Type	Rh Type	How Many Have It
O	positive	37.4%	44%
O	negative	6.6%
A	positive	35.7%	42%
A	negative	6.3%
B	positive	8.5%	10%
B	negative	1.5%
AB	positive	3.4%	4%
AB	negative	.6%

(Source: Stanford School of Medicine: Blood Center) 

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