The Week in Review
Week in review: Chip stock losses, P&G gain, and lower bond yields
Owning a single chipmaker directly carries its news in full, with nothing to offset it.
In the week ended Friday: S&P 500 −0.47%, Nasdaq-100 −0.79%, Dow +0.41%
Story of the week
Week of Oct. 19
Chip stocks end the week lower as AI financing and oil worries weigh
Chip stocks opened the week with a rebound on Monday. The iShares Semiconductor ETF, a fund of chipmaker shares, jumped 1.7%, ending the index's longest losing run since 2008. On Wednesday, Lam Research reported results after the close that narrowly beat estimates, yet its shares fell in late trading. Thursday brought the setback. The iShares fund tumbled 6.8%, and Lam Research tumbled 11.8%. Over the week, the chip fund tumbled 3.1%, while the Nasdaq-100 fell 0.8%.
Reports tied Thursday's selloff to higher oil prices and a broader retreat in technology shares. They also cited worries about how companies are paying for heavy spending on artificial intelligence. Coherent tumbled 12.5% that day and was among the hardest hit. Even after Monday's rebound, the chip index stayed well below its June record, according to reports. Broad index funds hold large chipmakers such as Nvidia and Micron Technology, and swings in the group could reach many retirement accounts. The S&P 500 fell 0.5% over the week.
For readers
What it means for you: People who own Lam Research shares directly carry its news in full, with no other holdings to offset it. The stock stands 46.9% below its 52-week high, after shares fell despite a narrow earnings beat. Reports tie the group's weakness partly to AI financing worries, and further news on that spending may move it again.
The week in markets
Week ended Friday
| Market | Fri close | Week | Year |
|---|---|---|---|
| S&P 500 | 7,623.68 | −0.47% | +11.37% |
| Nasdaq-100 | 28,957.53 | −0.79% | +14.68% |
| Dow | 52,215.16 | +0.41% | +8.64% |
| 10-Yr TreasuryWeek and year in basis points | 5.00% | −9 bp | +82 bp |
| Gold (GLD) | $366.61 | −4.03% | −7.49% |
| BitcoinAt 4 p.m. ET Friday | $81,167 | −0.37% | −7.25% |
Breadth. 59.7% of the 926 most heavily traded U.S.-listed stocks rose this week.
The S&P 500, day by day
Movers of the week
Large U.S.-listed companies
Sectors this week
Biggest gains
Roper Technologies ROP +14.48%. Rose after the company beat quarterly profit estimates and raised its full-year earnings forecast.
CrowdStrike Holdings CRWD +13.27% (+$30.97B in market value). Climbed after the cybersecurity company deepened its work with Nvidia to protect AI agents.
SERVICENOW NOW +11.97% (+$17.57B in market value). Rose after Bank of America raised its price target, citing demand for AI tools.
If you own
This week
Index funds may have felt Meta Platforms' slide, since they hold it in proportion to its size; its shares tumbled 9.4% and it lost $150 billion in market value. Large U.S.-listed companies overall fell 0.5% for the week, and one heavyweight's slide could pull on a broad index fund's return.
Bond funds may have gained ground, because bond prices move opposite to yields and the 10-year Treasury yield fell 9 basis points this week to 5.00%. A lower yield could lift the value of bonds a fund already holds, though new bonds it buys may pay slightly less income.
Gold funds tumbled 4.0% this week, leaving them with a loss of 7.5% so far this year. Because these funds tend to respond to real interest rates, meaning yields after inflation, and to the dollar, shifts in either could move them again.
Sector funds pulled in opposite directions this week: an energy sector fund jumped 1.6%, the best showing, while a communication services fund tumbled 4.4%, the worst. A portfolio tilted toward one industry could see returns far from the broad market's.
Need to know
The week’s top stories
- 1
Fri Nasdaq-100 slips as AI debt worries weigh before Fed meeting. The Nasdaq-100 fell on Friday as worries about the debt loads of AI infrastructure companies hit memory chip and cloud computing stocks. Reports said the cost of insuring CoreWeave's debt against default hit a record this week. Money moved into steadier defensive names such as utilities and consumer staples. Fed Chair Warsh declined to rule out an October rate increase. The Fed's two-day meeting begins Tuesday, Oct. 27.
- 2
Tue · Tech · −0.11% SpaceX holds a weekly gain after a choppy post-earnings run. SpaceX reported third-quarter revenue and earnings per share above analyst estimates after Tuesday's close. The shares surged 7.8% on Wednesday, then tumbled 9.1% on Thursday. By Friday's close the stock had gained 1.0% for the week. A company's results may have a modest effect on most broad index funds. The Fed's rate decision on Wednesday, Oct. 28 could matter more.
- 3
Wed · Tech · +0.47% Meta Platforms ends the week lower despite an earnings beat. Meta Platforms reported third-quarter revenue and adjusted earnings above analyst estimates after Wednesday's close. Revenue grew from a year earlier, and daily users across its apps increased. The shares then tumbled 7.0% on Thursday and slid 1.0% on Friday. For the week, the stock tumbled 9.4%. The Fed's rate decision on Wednesday, Oct. 28 could shape what cash savings pay next.
- 4
Thu · LEN · +8.69% Homebuilder stocks rally as lower Treasury yields ease mortgage worries. Homebuilder stocks rallied on Thursday as investors moved money out of AI-linked stocks and into Treasuries. The 10-year Treasury yield, a benchmark for mortgage rates, fell below a closely watched level. Lennar surged 8.7%. Not every property stock gained: CBRE Group tumbled 7.3% for the week. Lower mortgage quotes may follow only if the drop lasts, and the Fed's decision on Oct. 28 could test that.
- 5
Thu · PG · +5.58% Procter & Gamble holds a weekly gain after an earnings beat. Procter & Gamble surged 5.6% on Thursday after fiscal first-quarter profit and sales beat analysts' estimates. The maker of Tide, Gillette and Pampers also affirmed its fiscal 2027 outlook. The shares slid 2.8% on Friday but still gained 1.0% for the week. Reports noted margin pressure, which could test the company in the months ahead.
Chart of the week
Energy and health care led the week while communication services lagged
Each bar shows one sector fund's change over the week, from the strongest at the top to the weakest at the bottom. A sector fund holds the large companies in one part of the economy, such as energy or technology. Someone who owns a broad index fund holds all of these sectors at once, so the overall direction may matter more than the gap between them.
Source: market data, as of Friday's close.
AI corner
Three changes that matter
Topics: Regulation, Energy
Trump orders new AI data centers to produce their own power
The order could raise building costs for data center developers, and BlackRock's Larry Fink warned that slower construction could push up inflation, according to reports.
Topics: Startups
Anthropic draft stock listing filing shows a heavy loss from accounting charges
Most of the loss came from accounting charges tied to convertible notes, a type of debt that can turn into shares, while computing costs climbed, according to reports.
Topics: Chips, Deals
Amkor expands Nvidia chip packaging deal in South Korea
The companies said the agreement aims to expand advanced packaging, the step that assembles chips into finished AI processors, to meet rising demand for AI computing.
How it works
Risk
Many stocks can share one risk. Diversification means spreading money across many holdings so that a loss in any single one has a smaller effect on the whole. It can soften the ups and downs of a portfolio. It tends to work best when the holdings do not all react to the same news. In practice, a saver might own a fund that holds many companies. If a company reports bad results, the others may hold steady, and the fund barely moves. That protection depends on the companies being different from each other. A fund that owns a single industry spreads money across many names, but those names often share customers, costs and investor mood. When a worry hits the whole industry, most of them can fall together. The spread across companies then offers less cushion than it appears to. This week showed the gap. On Thursday, reports linked a broad chip selloff to higher oil prices, concerns about how AI spending is financed and a wider retreat in technology shares. Applied Materials tumbled 8.2% and AMD tumbled 8.1% the same day, and funds holding chip stocks fell with them. Savers whose retirement accounts lean heavily on a chip fund may have felt the full swing. The idea tends to matter again when a single theme drives a whole group of stocks, such as a shift in interest rates or a change in spending plans across an industry. Funds that hold many industries may soften such moves, though they cannot prevent losses when most markets fall at once.
The weekly close
The big picture. The S&P 500 fell 0.5% this week, leaving it up 11.4% for the year. Technology set the tone. Thursday's selloff in chip stocks, which reports tied to higher oil prices and worries about how companies pay for AI spending, outweighed earlier gains. Beneath the index, most stocks rose over the week, 59.7% of them, led by energy, health care and real estate. The 10-year Treasury yield fell 9 basis points to 5.00%. Lower yields tend to lift the prices of bonds a fund already holds.
Tomorrow: The Week Ahead, on the Fed's rate decision, consumer confidence and September new home sales.
Not investment advice.