Elon Musk's net worth fell $15 billion after Tesla's robotaxi event

Tesla's robotaxi event, at which the company debuted the long-anticipated  prototypes for its Cybercab and Robovan, failed to impress many investors and Wall Street analysts. 
The company's stock tumbled  in the aftermath — and with it, CEO Elon Musk's net worth.

Musk's net worth — which is partly  tied up in Tesla, as he holds about 13% of the company's stock — goes up and down along with the company's value.
And on Friday, Tesla's stock sank more than 9% from $238.77 to $217.80 per share.
According to the Bloomberg Billionaires Index, updated after the close of trading in New York, Musk's net worth fell by $15 billion. 

With a total net worth of $240 billion, Musk remains the richest man on earth.
Forbes reported in July that Musk faced a similar financial hit after the "We, Robot" event was delayed from its original August date, and Tesla stock tumbled about 7%.
 The company's stock value had continued its downward trend through early August then rebounded in September — bringing Musk's net worth to more than that of McDonald's and Pepsi.

However, Tesla shares had not yet returned to the year-to-date high they'd hit in July before the stock slumped again this week.
Musk will control more than 20% of Tesla shares if his massive pay package survives its ongoing legal challenges, which could increase his net worth.
Business Insider reported that the "We, Robot" event left many Wall Street analysts with more questions than answers about Tesla's robotaxi fleet.

Analysts criticized the lack of detail about the company's plan for self-driving vehicles and showed skepticism surrounding the proposed timelines for their widespread release. 
That lack of clarity and the absence of the long-promised, less-expensive Tesla could have contributed to the stock's decline.

Ref: Elon Musk's net worth fell $15 billion after Tesla's robotaxi event (yahoo)