The IQ scores of young people have begun to fall after rising steadily since the Second World War, according to the first authoritative study of the phenomenon.

The decline, which is equivalent to at least seven points per generation, is thought to have started with the cohort born in 1975, who reached adulthood in the early Nineties.

https://marginalrevolution.com/marginalrevolution/2018/06/reversal-flynn-effect-environmental.html#comments