No, I think there's a flaw or a logical problem with this method of calculation.
The fact is that the percentage of content on Facebook is not equivalent to percentage of revenues. People post billions upon billions of pieces of content to Facebook. Your average person, Canadian or Quebecker, can see close to 1,000 pieces of content per day. The majority of that content is seen by no one, because there's just too much content and too few hours in a day.