Here is a yearly measure for average # of ranked peaks (300' prominence) per outing for those who bag 20 or more peaks a year:
http://www.listsofjohn.com/PeakStats/Content/PPO.php
It includes repeats if you've logged them with dates.
This can be found from home page->Recent Content->Member's Peaks by Date Range with a link 'Peaks per outing leaders by year'.