Seeing as they get payed in base salary plus bonus, with the bonus being as big as the firm wants it to be, it varies.  If, for instance, he turns everyone's excel macros into lisp macros and makes half the firm redundant, all in the space of one year, and the boss miraculously not only forgives but praises him for it, he can get...yeah, a few million, really.  But I'm making no guarantees.