I was just looking at something similar. How I understood the results were the total evaluation time, not CPU time. There is a caveat somewhere about how the time will be thrown off if the machine goes to sleep. Here are the two pieces of relevance I have been using to compare the times.
To get the time as an integer…
average of evaluationcycle of client / 1000 * second / minute
To get it as a time interval…
average duration of evaluationcycle of client
Have you noticed the Enterprise Security Background Evaluations are taking way to long? That is what made me start researching all of this.