Taking Google as the average is throwing off your numbers by an incredible amount. Amazon alone has more employees (around 540k as of the most recent reporting I can find) than you gave the entire group. Microsoft and Apple each account for more than Google as well.
Does the Amazon number include people working in logistics, delivery, and all that? I suspect that is huge portion of that number. Their engineering force is larger than Google's but not by much, I think (60-70k at best).
