More and more companies are confirming that President Trump’s trade war is slowing down the global economy.

On Wednesday, Apple (AAPL) shocked markets when it said revenue in its holiday quarter would miss expectations.

This news sent Apple shares down as much as 7% after hours and confirmed the market’s biggest fear about the global economy — that trade is slowing down businesses around the globe.

“While we anticipated some challenges in key emerging markets, we did not foresee the magnitude of the economic deceleration, particularly in Greater China,” Apple CEO Tim Cook said in a letter to investors published after the market close on Wednesday.

“In fact, most of our revenue shortfall to our guidance, and over 100 percent of our year-over-year worldwide revenue decline, occurred in Greater China across iPhone, Mac and iPad.”

Apple now expects revenue will total $84 billion in its fiscal first quarter, below its initial guidance for revenue of $89-$93 billion the company gave Wall Street back in November.

Cook added to the gloomy view of China’s economy on Wednesday, adding, “China’s economy began to slow in the second half of 2018. The government-reported GDP growth during the September quarter was the second lowest in the last 25 years. We believe the economic environment in China has been further impacted by rising trade tensions with the United States.

“As the climate of mounting uncertainty weighed on financial markets, the effects appeared to reach consumers as well, with traffic to our retail stores and our channel partners in China declining as the quarter progressed. And market data has shown that the contraction in Greater China’s smartphone market has been particularly sharp.”

Slowing earnings growth, higher interest rates from the Federal Reserve, and slowing economic growth in the U.S. and around the world have all been cited as contributing to a fourth-quarter stock market decline that was the worst since the financial crisis.

But recent business surveys and commentary from corporate America has started to outline an economic environment which makes clear that trade tensions and President Donald Trump’s ongoing trade fight with China are at the root of the most acute stresses in the global economy.

In late December, FedEx (FDX) executives told investors that its international business had “weakened significantly since we last talked with you during our earnings call in September.” The company added that, “China's economy has weakened due in part to trade disputes.” FedEx cut its outlook for 2019 as a result.