Allen Press has released the 2013 Study of Subscription Prices for Scholarly Society Journals.
Here's an excerpt:
This study aims to provide information to society and association publishers on pricing and library budget trends, strategies libraries use for cost containment, content selection and cancellation criteria, access preferences, and user behavior.
The Allen Press panel and several other studies done in 2012 highlight that librarians use a variety of strategies to work within budgets that are not improving significantly. The following is a review of scholarly journal price trends during the past year. The data presented in this study summarize historical prices of approximately 200 publications appearing in the Allen Press Buyerâ€™s Guide to Scientific, Medical, and Scholarly Journals.