September is known as the worst month of the year for stocks, and so far it’s living up to that reputation — especially for Nvidia shareholders.

Global stock markets are awash in red on Wednesday, as fears of an economic slowdown in the United States rattle investors ahead of Friday’s pivotal jobs report.

Here’s the latest:

  • S&P 500 futures were down 0.3 percent in premarket trading.

  • Stocks in Asia and Europe broadly sold off on Wednesday.

  • Oil prices also fell as global growth concerns accelerated, and the price of Bitcoin dropped, nearing a one-month low.

That’s after a bad day for U.S. markets. The Nasdaq Composite fell 3.3 percent on Tuesday, with Nvidia leading the way: The chip maker plunged 9.5 percent, wiping $279 billion off its market cap — the biggest one-day decline for a U.S. stock ever — and dragging down the other artificial intelligence heavyweights that make up the so-called Magnificent Seven. (More on the chip maker’s woes below.)

The S&P 500 had its worst day since the Aug. 5 meltdown. Investors may be feeling some déjà vu. Last month’s rout was prompted in part by data that showed that the U.S. economy was losing steam. On Tuesday, weak manufacturing data renewed those concerns.

Economists still think a recession is unlikely, but a drip-drip of underwhelming growth data — especially in the labor market — has spooked some investors as the Fed weighs finally cutting interest rates. Up next: Investors will watch closely Wednesday’s JOLTS employment data, and the Fed’s Beige Book economic report.

The big focus is Friday’s payrolls report. Economists expect that employers added about 163,000 jobs in August. A softer number could compel the Fed “to cut by 50 basis points,” Andrew Hollenhorst, an economist at Citi, said on a webcast with clients on Tuesday. “We could have a lot of volatility on Friday, as we interpret the jobs report, and then as Fed officials interpret the jobs report,” he added.