Yes, I was wondering about those numbers. According to the numbers below the total of INTJs, INTPs, INFJs and INFPs is only 6% of the total population whereas the above numbers would make them 11% of the total population
BTW I got the below from this web page,(libertycorner.blogspot.com/2004/03/iq-and-personality.html - not a live link!) there is a bunch of interesting stuff there
In summary, here's what the statistics indicate about the correlation between personality traits and IQ:
Other personality traits being the same, an iNtuitive person (one who grasps patterns and seeks possibilities) is 27 times more likely to have a high IQ than a Sensing person (one who focuses on sensory details and the here-and-now).
Again, other traits being the same, an Introverted person is 8 times more likely to have a high IQ than one who is Extraverted; a Thinking (logic-oriented) person is 2.5 times more likely to have a high IQ than a Feeling (people-oriented) person; and a Judging person (one who seeks closure) is about twice as likely to have a high IQ than a Perceiving person (one who likes to keep his options open).
Moreover, if you encounter an INTJ (Introverted, iNtuitive, Thinking, Judging), there is a 37% probability that his IQ places him in the top 2 percent of the population. The probability is 20% for an INTP, 15% for an INFJ, and 8% for an INFP. These four types account for 66% of the high-IQ population but only 6% of the total population.