The Pulse

Takes the pulse on our favorite sim titles using online drivers as metric. Which sim has the most drivers?

Online players in the various titles. For iRacing, this is reported on the iRacing website, for the other titles it's steam.
Only lists PC, no console. Focused on simracing titles, although I've included Formula 1 in this instance. F1 and GT and simcade titles dwarfs PC simracing numbers, of course.
Numbers are sampled around 6 times each hour and averaged out.