China - 17 million more cars added to roads in 2014. Externalities: 7.5% of GDP.

The total social cost of Beijing’s dependence on motorised transport, including congestion and air pollution, is estimated at 7.5–15.0% of GDP. China added 17 million new cars in 2014
alone. In the United States, work by the New Climate Economy (NCE) demonstrates that urban sprawl costs over US$1 trillion per annum, including US$400 billion in costs to the public purse and more than US$600 billion in costs related to private vehicle use.