What You Don't Know

It came to my attention yet again recently that many grad students don't know that professors at many universities in the US are not paid by the university in the summer; we have 9-month base salaries. I have written about this before (I know, I say that a lot in this blog, but the blog is ~6 years old). I don't think it matters a lot if students know or don't know the details of how professors are paid except that it might help them understand the behavior of some professors in the summer.

Most of us don't take the summer "off", and most of us don't like being asked to do department service in the summer. Of course advising is a 12-month/year responsibility, but I know some professors who think nothing of spending lots of time working with their own grad students in the summer but balk at having to participate in a large number of prelim exams or defenses for our colleagues' students in the summer (a few here and there might be OK as long as the student is diligent about scheduling well in advance). etc. etc.

What I want to know is: if you are or have been a grad student in the US, do/did you know whether the professors have a 9-month or 12-month base salary? Does/Did it affect how you view/ed the types and amount of work that professors (including your advisor) do/did in the summer? Did you, or are you likely to, take a prelim or final exam in the summer and therefore need your committee to assemble?