Musk said he wants to form the America Party. A third party has never won the presidency, but they have influenced elections, experts say — mostly as spoilers.

Tesla stock lost nearly 7% Monday after Elon Musk announced plans of launching the “America Party.” William Blair downgraded TSLA shares.

Coming into Monday trading, Tesla stock was up 25% since the Nov. 5 election, down 22% year to date, up 17% since news that Musk was likely to leave DOGE in early April, and down 8% since a spat broke out between Trump and Musk on social media in early June.