|Sorry for the watermark - source|
The entirety of the context given for those numbers is this quote, "[b]oth districts said that's a jump over previous years."
The article also says that Ross Schools has to hire 12 new teachers, 8% of their district staff, which is, "fewer new faces than the last two years."
No hard numbers from previous years...no comparative numbers from other districts...no state-wide averages for districts of similar sizes (or even of not-so-similar sizes.)
From second-hand information, I've heard that Princeton City Schools have hired 58 new teachers district-wide this summer, about 18% of our district teaching staff (plus another seven administrators). Anecdotally it seems higher than in previous years, but I don't have any hard evidence to prove that.
Numbers without context aren't useful.
In this case, they're just evidence of lazy reporting.