116+
17 percent of the world population; superior I.Q.; appropriate average for individuals in professional occupations.

121+
10 percent; potentially gifted; average for college graduates

132+
2 percent; borderline genius; average I.Q. of most Ph.D. recipients

143+
1 percent; genius level; about average for Ph.D.’s in physics

158+
1 in 10,000; Nobel Prize winners

164+
1 in 30,000; Wolfgang Amadeus Mozart and the chess champion Bobby Fischer.