In 1949, teachers made up 70 percent of school staff. In 1969, teachers were 60 percent of school staff. The fraction of the education work force made up by teachers continues to fall and the most recent number–which is three years old–shows that teachers are now only half the staff. My guess is that this is not a good thing. Here’s the picture.
By the way, it’s not that we’re adding more central office administrators or more principals. Most of the instead-of-teacher hires are instructional aides, with further good dose of instructional coordinators in district offices.