In Peopleware, DeMarco and Lister write:

• Count on the best people outperforming the worst by about 10:1.
• Count on the best performer being about 2.5 times better than the median performer.
• Count on the half that are better-than-median performers outdoing the other half by more than 2:1.

What nearly everyone who has read that remembers is the following:

• The best people outperform the average by 10x.

Spot a difference?