October is living up to its ominous reputation among stock investors.

Stocks on Wall Street tumbled again on Thursday, as choppy early trading gave way to another bout of broad-based selling. The declines were widespread, touching everything from previously high-flying tech shares to usually insulated sectors like consumer staples and utilities.

When the dust settled, every sector of the Standard & Poor’s 500-stock index had dropped, leaving the stock market benchmark down an additional 2.1 percent. That slump followed Wednesday’s 3.3 percent decline, which was the market’s biggest dive in eight months.

So far in October — which looms large in the minds of investors as the month of the 1929 and 1987 crashes — stocks are down 6.4 percent. That puts the month on a pace to be the worst October for stocks since 2008, when they fell nearly 17 percent.

“Today it feels a lot more like there’s just money coming out of the market,” said John Linehan, chief investment officer for equities at T. Rowe Price in Baltimore. “I think there’s a level of anxiety about the market, especially given how far we’ve come.”