The S&P 500 ekes out a small gain to start the week, supported by strength from big tech

Stocks rose slightly as an advance in the biggest U.S. technology shares lifted the market into the green from losses earlier in the session.

The Dow Jones Industrial Average traded 0.1%, or 26.07 points, higher at 23,749.76 after being down as much as 360 points at one point. The S&P 500 rose 0.4%, or 12.03 points, to 2,842.74. The Nasdaq Composite climbed 1.2%, or 105.77 points, to 8,710.71, supported by strong gains in big tech stocks. Microsoft and Netflix jumped 2.4% and 3.0%, respectively, while Apple and Facebook both rose 1.4%.

The continued strength in tech outweighed losses in airline shares, following Warren Buffett’s comments over the weekend that his Berkshire Hathaway dumped the entirety of its stakes in the sector because of the coronavirus outbreak.

Airline shares were among the biggest losers in the S&P 500, with Delta, United, American Airlines all dropping more than 5%. Plane maker Boeing also fell 1.4%.

While Buffett was optimistic over the long term about the outlook for America, the move shows his concern that the pandemic has changed certain industries permanently and could be a sign that other investors are too optimistic about the economy returning to normal quickly.

“Mr. Buffett is a long-term investor, so his decision to sell reflects his belief that airline industry is facing future challenges that fundamentally change the value-capture of that business,” wrote Tom Lee of Fundstrat in a note to clients.

Disney fell more than 2% following a downgrade at MoffettNathanson. The firm said the economic hit to the entertainment giant will last longer than expected, with theme parks in particular facing a multi-year recovery.

More states are looking toward reopening nonessential businesses and easing stay-at-home orders as the new coronavirus cases slowed down over the weeks. California governor Gavin Newsom said Monday some businesses can reopen “as early as the end of this week.”

However, this easing comes as data from the World Health Organization showed the U.S. had its deadliest 24 hours of the outbreak between Thursday and Friday.

Meanwhile, tensions between China and the U.S. started brewing again over the origin of the virus. On Sunday, Secretary of State Mike Pompeo said there was a “significant amount of evidence” connecting the coronavirus to a lab in the Wuhan region of China.

Those comments came after National Economic Council Director Larry Kudlow said Friday that China will be “held accountable” for the coronavirus. Earlier in the week, President Donald Trump said he was considering imposing tariffs on China for its handling of the outbreak.

“We expect stocks to remain volatile as markets struggle to find a balance between announcements on the lifting of lockdowns, data on potential treatments and vaccines, economic releases, news on the course of the pandemic, and changing political dynamics,” Mark Haefele, chief investment officer at UBS Global Wealth Management, said in a note on Monday.

“The world has changed for the airlines. And I don’t know how it’s changed and I hope it corrects itself in a reasonably prompt way,” Buffett said Saturday from Berkshire’s first-ever virtual shareholder’s meeting.

Berkshire had more than $4 billion invested across United, American, Southwest, and Delta Airlines before the sale. Buffett noted his admiration for the industry but added there are events “on the lower levels of probabilities” that call for a change of plans.

Monday’s drop pushed American, United and Delta’s 2020 losses to more than 60%, while Southwest has lost nearly half of its value this year.

Berkshire also reported a record $137 billion in cash after the first quarter, but Buffett said he doesn’t “see anything that attractive” to deploy that money. Shares of Berkshire fell 2.5% on Monday.

Increasing hopes of a possible treatment from Gilead Sciences also lifted sentiment last month. On Sunday, CEO Daniel O’Day said remdesivir — Gilead’s promising antiviral drug — will be available to coronavirus patients this week.

Stocks notched their best monthly performance in over 30 years in April in part because of hopes of an economic reopening. Last month, the S&P 500 rallied 12.7%.

More than 3.5 million cases of Covid-19 have been confirmed globally, including over 1.1. million in the U.S. alone, according to data from Johns Hopkins University.

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Stocks rose slightly on Monday to start the week, as the advance in the biggest U.S. technology shares lifted the market higher.