Wischenbart.com publishes is annual ranking of publishers. Thank the Lord these numbers cannot be subject to the niggling of self-publishing fanatics, as they explicitly include only companies with revenues in excess of €150 million (c. $200 million).
I don’t detect signs of an industry in crisis in these numbers. McGraw-Hill is the only one not showing steady growth, and they are in the process of reorganization after acquisition. The chart showing evolution of revenues which can bee seen in their report shows a steady upward curve with a bit of a wobble in 2013. Note, for those who think “publishing” actually means “trade publishing”, that the trade publishing subset shows a similar bar graph.