Barclays slashed its S&P 500 target for 2020 as the coronavirus throws the global supply chains into chaos. The bank also expects U.S. companies to see an earnings decline this year.

The bank now sees the S&P 500 to end the year at 3,000, down from a previous forecast of 3,300. The equity benchmark tumbled more than 10% this week alone to 2,978 as of Thursday's close. More losses were expected Friday going by overnight futures.

"Even if the virus is fully contained in short order, the repercussions of the shock to the Chinese economy that has already happened to the rest of the world will not be insignificant," Maneesh Deshpande, head of equity derivatives strategy at Barclays, said in a note Friday. "We think it is too early to buy the dip since the repercussions from COVID-19 are likely to very bad or mildly bad."

Barclays also cut its S&P 500 earnings estimates to $162 per share this year, representing a 2% drop in profits. The call is even more pessimistic than Goldman Sachs' outlook on Thursday, which shocked the market. Goldman said it sees zero earnings growth for American companies in 2020.

"The drop in EM economic growth alone would lead to 2020 SPX earnings growth of ~ -2%, with the ripple through to other economies lowering it further," Deshpande added.

The forecast is far more bearish than the consensus forecast of Wall Street, which still calls for earnings to rise 7.7% this year, according to Refinitiv data as of Thursday.

Stocks are on pace for its worst week since the financial crisis as coronavirus fears continue to rattle the markets. The Dow plummeted nearly 1,200 points on Thursday — its biggest one-day point drop ever — closing in correction territory along with the S&P 500 and Nasdaq Composite.

"The magnitude of the drop in economic activity is tracking towards the more severe scenario outlined by our economists," Deshpande said.

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