(New York) The New York Stock Exchange closed lower on Friday, following a portfolio rotation toward technology, amplified by the massive computer outage that wreaked havoc at multiple companies around the world.

The Dow Jones Industrial Average fell 0.93% to 40,287.53, the tech-dominated NASDAQ lost 0.81% to 17,726.94 and the S&P 500, which closed out its worst week since April, fell 0.71% to 5,505.00.

An unprecedented computer outage hit part of the global economy on Friday as a result of a faulty update to Microsoft’s Windows operating system and antivirus software from US cybersecurity group CrowdStrike.

Grounded planes, chaos at airports, closed hospitals, disrupted urban transport in Europe: the computer virus responsible for this crisis has been identified and fixed, CrowdStrike reported, but many businesses were still experiencing outages on Friday evening.

Shares of US company CrowdStrike, which fell nearly 20% in pre-market trading, closed down 11.10% at $304.96.

Microsoft, one of the world’s largest stock markets, had previously lost 1.3%, but ultimately fell 0.74%.

The disruption has had a major impact on the airline industry worldwide. Shares of major US airlines, which had been in the red for much of the session, have finally recovered, including Delta (+1.18%) and United (+0.13%). Some 2,400 flights have been canceled in the United States so far.

“This collapse was a big factor” in the decline this session, said Tom Cahill of Ventura Wealth Management, interviewed by AFP.

“It was a tumultuous week,” as investment rotations out of big technology stocks sent the NASDAQ down about 4%.

Tom Cahill said the outage “certainly amplified the rotation,” which benefited the Russell 2000, the index of small- and mid-cap stocks, which rose 1.7% weekly.

Investors also reacted to Netflix’s results, whose shares were shunned (-1.51%) despite the market leader’s quarterly results in stream were better than expected.

Netflix beat Wall Street expectations with $9.56 billion in revenue, including $2.15 billion in net income. The California-based company also added 8 million subscribers to 277 million in the second quarter. But its forecast for future sales fell short of expectations.

American Express fell 2.74% as quarterly revenues disappointed at $16.33 billion, less than analysts had expected.

Starbucks rose 6.85% after a substantial share acquisition, the Wall Street Journalfrom activist shareholder Elliott Investment Management in the coffee chain, whose mobile drink ordering application was also disrupted by the computer outage linked to CrowdStrike and Microsoft.

Prepaid payments company Green Dot fell 5.70% to $9.26 after it was fined $44 million by the Federal Reserve for deceptive practices.

As the 10-year Treasury yield rose from 4.20% to 4.23%, the market remained nervous and alert to developments surrounding the US presidential campaign.

Tom Cahill stressed “the prevailing concern about the election outcome (…) in a market that has been primed for a correction for a long time.”

Donald Trump was officially nominated as the Republican candidate for the election during the party convention on Thursday evening. There is uncertainty about the fate of the candidacy of Democratic President Joe Biden.