Nasdaq Ends Its Worst Week Since June as Chip Stocks Slide and Oil Climbs Toward $110
The Nasdaq lost 4.5 percent over five days and the S&P 500 1.9 percent, while Brent touched its highest settle since May and the market's fear gauge jumped above 22.
Sunday, October 18, 2026/2 min read
Wall Street finished the week the way it spent it: lower, jumpier and looking over its shoulder at artificial intelligence. On Friday the Nasdaq composite fell 2.1 percent, closing a five-day slide of 4.5 percent that made it the index's worst week since June.
The S&P 500 dropped 1.1 percent to 7,659.44, and the Dow Jones Industrial Average lost 0.3 percent to 52,002.41, according to the market tables carried by La Nación. The Nasdaq closed at 26,140.03. For the week the S&P 500 fell 1.9 percent, also its worst since June, while the Dow actually gained 0.7 percent. The Russell 2000 of smaller companies lost 1.7 percent on the day and 3 percent on the week.
Why did chip stocks fall on Friday?
Chip companies gave back more ground as worries deepened about how long the AI building boom can last. Micron Technology fell 5.6 percent and Intel 5.8 percent. The VanEck Semiconductor ETF lost 3 percent on the day and 10 percent on the week, its sharpest weekly drop since April 2025, Dimsum Daily reported, citing worries about Chinese competition and a broader pullback from AI-linked shares.
The week's trigger was inflation. The hot September inflation report reset expectations for interest rates, and the stocks that borrowed most to build AI capacity took the hardest hits. Shares of CoreWeave fell nearly 12 percent on Friday alone and about 25 percent over the week, per the same report.
What is oil doing?
Oil provided the other half of the story. Brent crude settled at $109.86 a barrel, up 3.7 percent on the day and the first time it has touched $110 since May, with US West Texas Intermediate up 3.5 percent to $101.41. Energy stocks gained, and Chevron was among the winners. Higher crude also cushioned the Dow, which explains why it ended the week in the black while the Nasdaq did not.
The driver is the Gulf. Shipping attacks around the Strait of Hormuz and Houthi strikes on Saudi Arabia have kept supply nerves high all month. Every extra dollar on a barrel of crude feeds the inflation worry that is already hurting growth stocks.
Is the market scared?
Somewhat. The Cboe Volatility Index rose above 22 for the first time in four months. That is elevated, though far from panic. The S&P 500 is still up 11.9 percent for the year and the Nasdaq up 12.5 percent, according to the market tables. European and Asian markets closed higher on Friday, which suggests the damage was concentrated in American technology.
What to watch in the week ahead
The Federal Reserve meets on 27 and 28 October. Futures imply about an 82 percent chance that rates stay unchanged, per Dimsum Daily, after Fed Chair Kevin Warsh avoided signalling any near-term move. Traders will also watch whether oil holds above $100. Another week like this one and the question will shift from whether the AI trade is wobbling to who is paying for it.
Published in The Outspoken Digest
Editorial desk
Outspoken Digest Markets DeskReports for The Outspoken Digest across Business, Crypto.
Newsletter
The Digest, in your inbox
One edition, sent when it is ready. No noise, and your address is never passed on.
Read Next
More Business →
CoreWeave Shares Fall 25 Percent in a Week as Its Bonds Flash Warning Signs for AI's Borrowers
Oct 18, 2026/2 min read
ECB Clears UniCredit to Go Past 30 Percent of Commerzbank, Opening the Way to Control by Year-End
Oct 17, 2026/2 min read
Indonesian Stocks Plunge Nearly 12 Percent, the Worst Day Since 1998, After MSCI Floats a Downgrade to Standalone Status
Oct 16, 2026/2 min read
Kospi Plunges Almost 8 Percent and the Nikkei Falls 5 Percent as the Tech Sell-Off Spreads to Asia
Oct 15, 2026/2 min read