US stock index futures fell in overnight trading as an increase in speculative trading by retailers continued to drive hedge funds to take risks and investors worried about a market bubble. The losses build on last week’s decline, the worst for the market since October.

Futures contracts linked to the Dow Jones Industrial Average fell 270 points, indicating a 271 point loss on the opening bell. S&P 500 futures were down 1% while Nasdaq 100 futures were down 1.2%.

The Dow fell 620 points, or 2%, on Friday, closing below 30,000 for the first time since December. The Nasdaq Composite was also down 2% while the S&P 500 was down 1.9%.

During the week, all three major averages fell more than 3% for their worst weekly performance since October. The Dow and S&P also posted losses for January – the first negative month in four years – although the Nasdaq managed to post a profit for the month.

Friday’s slump came amid a plethora of retail investor activity in sharply shortened stocks like GameStop and AMC Entertainment, which fueled concerns over the general health of the market. Goldman Sachs noted that the current short squeeze is the worst in 25 years.

“This week’s events may have turned the markets upside down, but indicators of fear are suggesting we may have seen the worst of the breach,” Jefferies wrote in a note to clients over the weekend. Barclays added that the impact of the brief shortages is unlikely to affect the broader market.

“The ongoing short squeeze of some stocks by retail investors has raised concerns about wider contagion,” the company wrote in a recent statement to customers. “While we believe there will be more pain, we remain optimistic that it will likely stay local.”

Meanwhile, a group of 10 Republican senators sent a letter to President Joe Biden on Sunday asking him to consider a smaller, scaled-down Covid-19 aid proposal. Its current plans include additional fiscal incentives of $ 1.9 trillion. The alternative proposal comes after House Spokeswoman Nancy Pelosi said the house would pass a budget resolution, the first step in approving laws through reconciliation. The process would allow Senate Democrats to approve a relief effort with no GOP votes.

99 S&P companies are waiting for another busy week of wins. Alphabet, Amazon, Alibaba, Snap, Exxon, Biogen, Pfizer, and Chipotle are among the names to be released in the coming week. Thursday is the busiest day of the winning season.

“We believe the medium-term path for the market remains higher,” said Mark Haefele, global CIO at UBS Wealth Management. “In a pattern similar to the previous two quarters, corporate earnings for the fourth quarter of 20 are well above expectations.”

He added that a stimulus package, as well as investors going beyond delays in the manufacture and distribution of vaccines, should continue to boost inventories.

– CNBC’s Jacob Pramuk contributed to the coverage.

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