September is living up to its nasty reputation as the stock market’s most troublesome month, even as the Federal Reserve prepares to finally deliver a long-awaited interest rate cut the week after next.

What’s eating investors is that they fear, but don’t know for sure, whether the monetary easing has been a little too long-awaited.

“I think that the Federal Reserve is late in cutting interest rates, but Jerome Powell will be forgiven a lot of mistakes if he avoids a recession, which at this stage is still unknowable,” said Ivan Martchev, investment strategist at Navellier & Associates, in a note, referring to the Fed chair.

The S&P 500 SPX slumped 4.3% in a holiday-shortened week after U.S. investors returned from the Labor Day holiday, while the Dow Jones Industrial Average DJIA shed 2.9% — making for the worst week for both indexes since March 2023. Technology stocks took it on the chin, with the Nasdaq Composite COMP slumping 5.8% for the worst weekly performance since January 2022.

As was the case during an earlier growth scare at the beginning of August, a run of weak economic data was blamed for the market pullback. While not uniformly gloomy, investors appeared spooked by another weak Institute for Supply Management manufacturing sector gauge, while evidence of growth in the much larger services sector did little to lift the gloom.

But the main event — Friday’s August jobs report — proved inconclusive. The Fed had already signaled it was teeing up a Sept. 18 rate cut, the only question being whether it would be 25 basis points or 50 basis points. Fed watchers expected the jobs data to quickly settle the debate.