How many fights / violent incidents do you break up in a year?

For perspective - Middle years is where most of my teaching lies. This year I've broken up a few fights, and have had a chair nearly thrown my way this year. I've been sworn at very angrily as well. I also did some emergency support phoning while other teachers were holding a violent student.

I'd like to say there are reasonable consequences but there are not. Usually kids are gone for a few days but then are back causing problems again.