What percentage of people have 20/20 vision?

Less than half. Based on the national health and nutrition examination survey, a population survey of 12, 000 men and women 20 or older conducted between 1999 and 2004, less than half of U.S. Adults had 20/20 vision. Based on those surveyed, 3.6% were farsighted, about 33% were nearsighted, and about 36% were found to have some form of astigmatism.