SAN FRANCISCO, California -- Tesla shares dropped nearly nine percent after the New York Times reported stress is taking a heavy toll on CEO Elon Musk.
In the devastating report, Musk told the Times he has been working up to 120 hours a week and taking Ambien to get to sleep.
Musk created a stir last week when he tweeted that he wanted to take Tesla private.
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Tesla closed at $305 a share, down 30 points Friday.
This week alone Tesla has lost $8 billion in shareholder value.
Tesla stock drops after Elon Musk describes his 'excruciating' year