The WSJ had a story today on other leaders of NYC non profits - all but one made far more than Mary did at NYRR
total comp seemed to average around $800k/year although some of that was in housing and whatnot.
median base a little lower than that
so if her total comp was in the $500k range...that might be one reason she left - she was probably underpaid compared to her peers.
Although I don't know how the NYRR job is compared to say the museum of natural history.
http://www.wsj.com/articles/high-pay-for-nycs-cultural-leaders-1435081507