Tesla (TSLA) stock’s 4% rally today didn’t prevent Elon Musk’s electric vehicle-maker from logging its worst month ever, as the post-election rally disappears and the automakers’s market value holds below $1 trillion.

Tesla stock was—very—weak again Tuesday as investors digested early-year sales data, trying to determine whether a drop was due to random fluctuations or something more serious.It’s still too early to tell,

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