Originally Posted by
EricH
Pharoah's suggestion is a good one, but you might be able to get this information easier if an airline or airport would let you review security camera footage (which I assume exists).
Since it's generally possible to observe the entry of persons into the passenger security screening lines, there are data collection points that don't require viewing camera footage.
But given the passenger size demographics actually vary tremendously in the US by regions of some sort or another, and as passenger demographics are not the same at all times of the day/week/year, the utility of the data may be better for the OP's purpose if the data collection were done across multiple airports and at various times of the day/year.