In the United States, it is estimated that 2-6% of the population has red hair. This would give the U.S. the largest population of redheads in the world, at 6 to 18 million, compared to approximately 650,000 in Scotland and 420,000 in Ireland
大概是说,美国有2-6%的人是红头发这使得美国有600万到1800万人是红头发,比苏格兰的65万红发和爱尔兰的45红发还要多。