I think it's 99.7% within three standard deviations (e.g., in either direction) so presumably half as many are three standard deviations above the mean—99.85% (

I think it's 99.7% within three standard deviations (e.g., in either direction) so presumably half as many are three standard deviations above the mean—99.85% (top 0.15%). Tiny % either way.