Eductional level is now a poor measure of intelligence: Pjgoober wondered if the correlation between IQ and education has declined over the past few decades, which might explain why the association between educational levels of spouses has evidently not been rising. Indeed, according to the GSS, the correlation has fallen sharply in the past 30 years from .59 to .39. The overall trend held for both whites and blacks. One's educational level is now a poor marker of intelligence.