Very, very difficult to get anything more out of them that the listed min/mean/max in the contracts. The W2's tell the real story, at least here.

http://www.masslive.com/news/index.ssf/2012/02/data_from_salary_database_of_m.html

Experience hath shewn, that even under the best forms of government those entrusted with power have, in time, and by slow operations, perverted it into tyranny.
Thomas Jefferson