Informa, the multinational conglomerate owner of publishing brands including Taylor & Francis & Routledge, report that their academic publishing division earned an adjusted operating margin (profit) of 35.7% in 2013, or approximately 218 million USD in profits.
from Informa 2013 Annual Report:
http://www.informa.com/Documents/Investor%20Relations/Annual%20Report%202013/Informa%20plc%20Annual%20Report%20Accounts%202013.pdf
p.20:
Academic publishing: 367.1 million GBP = 616 million USD
Adjusted operating profit: 130.9 million GBP = 218 million USD
Adjusted operating margin 35.7%
Of course, that's after paying expenses - such as paying the basic salary of 770,000 GBP (1.3 million USD) to the Executive Director (p. 56) (not counting benefits, of course - like 25% of base salary towards pension and the 20,000 GBP car allowance.