Apple's worst day on Wall Street has investors feeling anxious

PALO ALTO, Calif. (KGO) -- There was a steep sell-off on Wall Street Thursday. The Dow dropped 660-points. One of the big reasons was Apple. The tech giant had its worst day in six years, plummeting 10 percent and losing more than $74 billion in value.

There is all sorts of anxiety about Apple as a result. But, it's not just about Thursday's drop. It's what happened between Thursday and October when the stock was at an all-time high, that has people concerned.

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Apple's stock has fallen nearly 40 percent since it's peak three months ago at $232 a share, which has given rise to concern that the iPhone, which accounts for 60 percent of the tech giant's sales, is losing it's luster.

"I'm fully in the Apple ecosystem. I have the watch, the phone, everything," said Stanford student J.P. Reilly, a loyal Apple customer, who did not buy a new iPhone when Apple rolled out their new models in the Fall of 2018. "The one I have now is perfectly fine and I couldn't see myself shelling out another grand for that."

Smartphone customers in China may feel the same way. Though Apple CEO Tim Cook blamed China's slowing economy and growing trade tensions between the U.S. and China, for driving down traffic to its retail stores.

Professor Anna Han is an expert on China trade at Santa Clara University School of Law.

"The consumers in China, because they are feeling the impact of the trade war, they're being more cautious about their spending."

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"A company that's built on just selling more and more iPhones eventually reaches a limit," said John Gunn, who is the former CEO and Chairman of Dodge and Cox, a large San Francisco investment firm.

Gunn was not surprised by Apple's trade-off. He says people should worry less about short-term volatility.

"Apple is enormously well-financed and so is not going to disappear at all. They'll battle back."

And that may be true. Reilly didn't buy a new iPhone, but he did buy an Apple watch this week. And, Apple does have a history of surviving and then thriving after big hits to their stock price.