2.2% of population falling below IQ range of 70 are termed as:

Intellectually disabled

The mean IQ score in a population is 100. People with IQ scores in the range of 90–110 have normal intelligence. Those with IQ below 70 are suspected to have ‘intellectual disability’, while persons with IQ above 130 are considered to have exceptional talents.

Classification of People on the Basis of IQ

 IQ Range                   Descriptive Label                    Per cent in the Population

Above 130                    Very superior                                     2.2

120 – 130                       Superior                                         6.7

110 – 119                      High average                                   16.1

90 – 109                        Average                                         50.0

80 – 89                            Low average                                16.1

70 – 79                          Borderline                                      6.7

Below 70                        Intellectually disabled                       2.2