Bonuses also make pay lumpy, so employees wanting to quit have to wait for the next bonus date or walk away from X% of their income. Bonuses are also often late, so X is never 0 no matter when you quit.
The median in the sibling comment wouldn't work because unless bonuses are paid monthly the median will just be the base salary, so you'd have to do mean.
you could tailor it as appropriate, but also there should be legislation that limits the ability to call "bonuses" bonuses rather than regular income - if nothing else I believe withholding on bonuses is 50% vs. a sane rate that is closer to what you'd be paying if you're on a minimum-is wage job.
The median in the sibling comment wouldn't work because unless bonuses are paid monthly the median will just be the base salary, so you'd have to do mean.