Shares of Fiat Chrysler Automobiles (NYSE:FCAU) were down about 36% as of 11 a.m. ET on Monday, Jan. 4.
So what's happening?
Before the market opened on Monday morning, FCA announced that the spinoff of its 90% stake in Ferrari (NYSE:RACE) had been completed as of Jan. 3.
Existing FCA shareholders will receive one share of Ferrari for every 10 FCA shares they hold. FCA closed at $13.99 on Thursday, and Ferrari closed at $48. Given that, we'd expect FCA's share price to drop by 1/10th of Ferrari's share price, or $4.80, as soon as the separation was official.
That's pretty much what happened.