Abuurrahman and Hareni, I do not have the figures.
From what I can tell, polytechnic lecturers get only decent salaries, somewhere between the medians of managers and professionals.
That said, tutors in universities make even lower. But assistant professors get a starting pay of somewhere close to $10k/mth. Associate professors and full professors obviously make more, maybe with $20k to $25k as the limit.
Anyone reading this please feel free to correct me if I'm wrong.