I'm wondering to which extent the uneven distribution of Tesla cars around the world lowers the cost of recalling them (i.e. I suspect 50% of them live in a 10-mile radius of Palo Alto :) )
I've been kind of shocked at how many Model S cars drive on the roads in Chicago, even in the dead of winter with (2 years ago) -17 degrees F. My wife and I count them on the way to work and generally see 3 every morning at least.
There is a Tesla owner down the road from me who keeps his outside all year. I live in Calgary, Alberta. It was -14F last night...
50% of them have been sold outside the US so your estimate might be a bit high.