Tesla’s TSLA stock, which surged 91% after President Donald Trump’s re-election, has collapsed by 44% since hitting an all-time high of $479.86 on December 17, according to data from Google Finance. Now trading at $302.

Ross Gerber, a longtime Tesla shareholder, outlined to BI four reasons he thinks the stock is vulnerable to a 50% pullback this year.

Tesla stock slid 8.4% Tuesday, dropping the company's market capitalization below $1 trillion for the first time since Nov. 14. The decline followed new data showing Tesla had a terrible January in Europe.