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- Tesla shares slid 7% early on Thursday after the EV maker fell short on details at its investor day.
- CEO Elon Musk was tight-lipped on details about new models after hopes built for a $25,000 car.
- Tesla said it plans to cut production costs in half to reach its goal of selling 20 million EVs a year by 2030.
Tesla shares fell 7% Thursday, after the automaker's much-anticipated investor day failed to live up to hopes for details of its next generation of cars and a rumored sub-$30,000 model.