|IQ test chart|
In 1916 Lewis Terman developed the notion of IQ and a corresponding scale. The intelligence quotient attempts to define the capacity and power of the brain in unambiguous terms.
The average person has an IQ score of 100. Scores over 140 are considered in the genius range. Only one percent of the people in the world have a score of over 135. Superior intelligence is around 115.
In a normal bell curve, 50 percent of IQs fall into the 90 to 110 range. Only 5 percent of the population has an IQ below 70.
About 1 in 400 people have an IQ considered genius (140 to 145). Nobel Prize winners usually fall in the 155 to 164 range. Anything above 140 is considered a genius. After a score of 200, the genius is immeasurable.