YBP has released its annual book price update, based on data from their fiscal year of July 1, 2011 - June 30, 2012. This is good information for academic libraries managing budgets and trying to plan spending.
Most interesting is that the average book price for cloth books is $83.59USD, and book prices are up 3.2%. Also, ebook prices from the aggregators that YBP uses (ebrary, Ebsco and EBL) averaged $95.14USD, a decrease of 2% from the previous year.
YBP predicts a 3-4% increase in the cost of both academic print and e-books for this fiscal year.