Who did an actual body count to arrive at this 8 million figure? Or is this just a guesstimate based on a survey configured according to the parameters cooked up by digital models. You know, kinda like global warming.
There are a known number of rooms, so it was probably just a matter of counting up how many in a fraction of one or more rooms, and estimating the count that way.
Counted tirelessly by a million government workers, one by one, at a $15 hourly wage. (It was the coffee breaks that padded the time frame.)