NIO overtakes BYD as most valuable Chinese automaker, is this a bubble?

On November 27, NIO rose 0.58% to $54, bringing its year-to-date gain to 1243%. It has a market capitalization of $72.84 billion (RMB 478.84 billion), surpassing BYD's RMB 474.9 billion to become the auto company with the highest market capitalization in China.