
Actual source:
Bottom right it says OICA, which is the ‘International Organization for Motor Vehicle Manufacturers’ and the numbers correspond to total motor vehicle productions (not just passenger cars, at least for most regions) for 2024:
https://oica.net/wp-content/uploads/2025/10/By-country-region-2024.pdf









Looking at the blackbody radiation temperature color relationship from Wikipedia, I’d say the color roughly corresponds to 2500K ~ 2300°C ~ 4000°F
The red outside would have to be at least ~800K ~ 500°C ~ 1000°F