3:00-4:00 AM: Drunks of all sorts, club kids, and winos. Late night workers, busboys, getting off their shifts. Only a handful of people per car. 6:1 male/female ratio.Link (via Kottke)
4:00-5:00 AM: Transit workers changing shifts. Maybe 6 people per car. All male.
5:00 AM - 6:00 AM: Blue-collar laborers, minorities, immigrants. Half the car is asleep. Maybe 20 or 25 people per car. 9:1 male/female ratio.
6:00 AM - 7:00 AM: Construction workers, blue-collar laborers, hospital workers. 75% of seats in car are taken. 7:3 male/female ratio.