Model S fires could be compared to Nissan Leaf fires, as they're both electric cars. Although Leaf is sold massively more than the Model S (Leaf is the most produced electric car in history).
Where are you getting your numbers from? The volt sold more than the leaf in 2012 by almost double. At best the leaf sells about 1500 a month. The model S is well over 3k a month as well. so I would like to see your sources on the matter.