I KNOW this survey has to be BS...putting Russia, a powerhouse in math, that low, something is obviously wrong.
Russians actually don't do too well in terms of IQ tests relative to other Europeans. The high level of alcoholism and low level of economic achievement of the Russian population grow out of the lack of cognitive ability.
There were quantitatively gifted Russians at one time: they were called Jews (and Latvians, Estonians).