After I was done with my talk, I returned the data behind one of my key slides to reassure myself that it was sound and realized that it wasn't.
I noticed from our Google Analytics dashboard that our traffic to the library's front page appeared to slowly ebbing downward.
To illustrate this drop, I chose a random day in October 2007 and a random day in October 2009 and there was about a 30% difference between the two. But, on closer inspection, I realized that there was a drop in traffic in October 2009 during the University of Windsor's first Fall Break (called UWin week) which probably exaggerated the results.
So, in these updated slides, I compared the traffic of the entire site (that Google Analytics can understand) for the entire month of November. And I found out that November 2009 had 88% of the traffic of November 2007.