I got 17 too, missed new zealand, malta and brunei. Of the other ones I think austria somehow surprised me the most, I think of snow and mountains, so less room for cars haha. And france/netherlands/belgium werent there while germany on one end and spain on the other end were there. And luxembourg,
Even though it is probably an error on the wikipedia page, there are probably more than 683 000 cars in the country.
https://www.acea.be/statistics/tag/category/vehicles-per-capita-by-country It is still not extremely recent, 2016 but it is atleast more recent for over half of the countries that made it to the top20 in this quiz, most of which use 2015 data. Plus (seemingly) having used the same year for a the countries makes it a lot fairer, compared to data gaps of 5+ years.
It is 2017 data (has been updated last in 2019, so seemingly no more recent data s available)
just like in the previous link finland has risen a lot, to number 3 in 2017. And netherlands and belgium join the top 20. Ow... but it is statistics only on europe... Still.. major changes fromt the 2015 data
1 am now.. so any more research now would be counterproductive I think.. would mainly be my head on the keyboard haha.