Does that version of North America include Mexico City? I'm sure it does, but it is probably fairly up there too.
It's quite a bit lower at 17 Million.
YYZs recent growth is a combination of joint venture agreements (which make it beneficial for United to push customers onto Air Canada transatlantic flights) and Pearson offering a fixed-price on landing fees to Air Canada (and WestJet) when they hit growth targets. Each USA <-> Europe passenger is +2 for the International count at YYZ. JFK gaining the same passenger is only +1.