Tesla Inc. shares dropped as much as 6.2% in U.S. pre-market trading on Tuesday, extending an early decline that began with a 5.2% slide shortly after markets opened for electronic dealings. The move, if sustained at the cash open, would wipe about $7 billion from Chief Executive Officer Elon Musk’s personal fortune, according to calculations cited by Axios. Traders pointed to expectations of disappointing forthcoming figures as a catalyst for the sell-off, though the company has not released any new financial information since its last quarterly report.