I don't have that in front of me right now. It's not insignificant. Also, the way people use it, they use it selectively. They may have specific searches that they don't want any record being held, or they may simply, as I explained, be using a device they do not have usual control over. They choose to use that tool, so there's no trace left of their usage on the machine itself.
On October 30th, 2012. See this statement in context.