Ford Motor’s pre-released third quarter earnings report warned investors of $1 billion in unexpected supplier costs.

The automaker’s stock prices plummeted with the news.

In fact, Ford Motor stock saw its worst day in 11 years. Shares closed Tuesday at $13.09 apiece, down by 12.3%, shaving $7 billion off the automaker’s market value.

Ford announced earlier this week that supply problems led to parts shortages that affect up to 50,000 vehicles, mostly high-margin trucks and SUVs. Ford expects to complete unfinished vehicles and dispatch them to dealers in the fourth quarter.

Ford reaffirmed its forecasts for the year but set expectations for third-quarter adjusted earnings before interest and taxes at between $1.4 billion to $1.7 billion. Those figures are significantly below the forecasts of some analysts, who were projecting quarterly profit closer to $3 billion.

No major Wall Street analysts have downgraded the stock in response, but some suggested they were surprised by the announcement. Most believed supply chain issues had eased and Ford was navigating the crisis better than some competitors.

BofA Securities analyst John Murphy said in a note to investors on Tuesday: “Ultimately, this news is somewhat surprising as broader macro news suggest supply chains have gotten incrementally better over the last few months.”

Several analysts also questioned whether this was a Ford-specific problem or an indicator of industry-wide problems in the automotive industry.

But companies like GM report improvements.

“We are seeing an improved situation,” GM CEO Mary Barra told CNBC. “We keep working, solving issues, looking for efficiencies as a normal course, and we’re going to continue to do that.”

She also indicated GM is on track to complete the manufacturer of about 95,000 vehicles lacking certain components due to supply chain problems. GM warned investors in July that supply chain issues would materially affect its second-quarter earnings.

Ford spokesman T.R. Reid told CNBC that the company continues to deliver on its Ford+ restructuring plan.

 “We’ve got a great plan at Ford+ to create value for customers, and investors and other stakeholders over time,” he said.  “It’s our obligation to execute against it and create that opportunity.”

Overall, Ford stock value has fallen over 36% year to date but is still up about 2% for the last 12 months.