A combination of positive coronavirus vaccine data and a rising number of cases left the market trapped in a seesaw this past week, preventing it from making a meaningful move one way or the other.
The Dow Jones Industrial Average fell 0.7% for the week, and the S&P 500 lost 0.8% in that time period. That marked the Dow's and S&P 500's first weekly declines in three weeks. The Nasdaq Composite, meanwhile, eked out a small one-week gain.
The market's muted performance came as the rate of new Covid-19 infections hit an all-time high in the U.S.
And many states have rolled back reopening plans and implemented fresh restrictions to curb the spread.
At the same time, the latest data on potential coronavirus vaccine candidates has raised expectations of a strong economic recovery further down the road.
The University of Oxford and AstraZeneca said Thursday their Covid-19 vaccine was safe, and it triggered a similar immune response among all adults. Meanwhile, Pfizer and BioNTech said they applied for an emergency use authorization for their vaccine from the Food and Drug Administration.
"COVID-19 is pulling financial markets in two opposite directions," strategists at MarketDesk Research wrote in a note. "On one end of the spectrum are positive vaccine trial results. On the other end of the spectrum are rising COVID-19 cases."
The stock market's back and forth could continue in the week ahead as investors digest even more headlines related to the outbreak and potential vaccines, CNBC's Patti Domm writes.
And Mike Santoli points out that there are some under-the-radar forces investors might not be thinking about that could trip up the market into year end.
Next week will be a short one on Wall Street, with the markets closed on Thursday for the Thanksgiving holiday and Friday's session ending early.
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