In the early 1980s, the average IQ in the USA was 100, when the population was 270 million.
By 2010, the average IQ in the USA had dropped to 98, with the population having increased to 320 million.
For a population this large, that represents a plunge into the abyss. Immigration into the USA is overwhelmingly weighted toward the lower IQ masses from third-world cesspools.
Perhaps you have, but, if not, read “The Bell Curve” which describes the findings of many studies regarding IQ, poverty, socio-economic status, race, criminality, employment /unemployment, illegitimacy.
When the book was written about 30 yrs ago the howls from “...the mongrel dogs who teach” were deafening from the Usual Suspects because it dared to show that study after study (almost all by liberals) showed definite differences in the races’ IQs.
At the top was the Jews about a standard deviation from the mean, 10-15 pts on the test.
It also describes how a new “cognitive elite” is forming from the natural forces of technology and testing. Intelligent children are highly tested and those within the top five or ten percent are sought out by the elite universities
Those in scientific and medical fields and the students at the best schools come overwhelmingly from that tiny portion of this cognitive elite.
It is very depressing.