From the Blog Post:
[The chart] tracks annual totals for page hits, title count, and institutional subscribers to HEB for 2007 through 2012.
The chart shows that the number of total annual hits has increased significantly more steeply than both the number of subscribers and titles, which seems to indicate that interest and usage among existing subscribers have continued to grow over time, and that our subscribers may be getting more out of the resource the longer they have access.
Humanities E-Book will add 300 new titles to their collection this summer.
Access Blog Post and Chart
Direct to ACLS Humanities Ebook Web Site