I saw it on one of the thread the comment that only about half the people have average or better intelligence....
The infamous "Bell Curve", below. The number in the middle, 100 (the mean) is dead average IQ. This is where most of the people score, as indicated by the height of the aqua curve. Therefore, half of the population is at 100 or above, and half at 100 or below. Rather simplistic, because the Average *range* is between 85 and 115, which is where 68% of the population falls. Those with IQs between 115 and 130, comprise only 13.59% of the population. These are the "smarter than average" folks. Those above 130 are gifted, and only comprise a little more than 2% of the population. The same is true for the bottom half of the curve, but in reverse: 13.59% of the population score between 85 and 70, which is "slow". Scores of 70 and below, 2.27% of the population, are intellectually impaired.