The Market's Split Personality: Nine Sectors Rose in a Down Week While Tech Lost $5 Trillion Since October 6

A down week that was not a broad selloff

Last week looked like a rout on the headlines — the S&P 500 down about 0.6 percent, the Dow down less than 1 percent, the Nasdaq down 2 percent, and Friday alone taking the Nasdaq down 2.86 percent, its worst single day since June, with the S&P 500 down 1.82 percent and the Dow down 1.09 percent. But underneath, the market split in two. Nine of the eleven S&P 500 sectors gained 1 percent or more during the week — an internal pattern not seen in any down week for the index since at least 1999. In other words, most of the market rose while the headline indexes fell, because the damage was concentrated in the handful of giant technology and semiconductor names that dominate index weights. It was a rotation out of one trade, not a vote against stocks in general.

The $5 trillion tech slide

The concentration is the story. The largest AI and semiconductor stocks shed about $5 trillion in market value since October 6, as concerns about artificial-intelligence capital expenditure pressed on the sector. Selling resumed late last week after Alphabet and Microsoft issued lower-than-expected capex forecasts, while Amazon maintained its full-year guidance. Intel became the week's emblem: its shares fell about 29 percent on Friday, their steepest one-day decline since 1974, after third-quarter revenue of $16.51 billion (up 21 percent year over year) and earnings of 52 cents per share were paired with fourth-quarter revenue guidance of $15–16 billion, below estimates near $17 billion, and an expected 25–30 percent fall in PC shipments from the prior quarter. For October as a whole, the Nasdaq logged its worst monthly decline since March 2025.

Monday's tentative reset

Futures pointed to a calmer open on Monday, November 2: Nasdaq-100 futures up 0.84 percent, S&P 500 futures up 0.51 percent and Dow futures up 0.55 percent as of 5:38 a.m. ET, while US crude fell below $100 a barrel on hopes of a diplomatic path in the US-Iran standoff. The week ahead is crowded: Apple reports after Monday's close — the company finished Friday worth about $5.03 trillion against Nvidia's roughly $4.93 trillion, up about 27 percent year to date against the S&P 500's 11 percent — Palantir also reports Monday, AMD reports Tuesday, and the October jobs report lands Friday, with economists polled expecting a gain of 55,000 jobs. Tuesday's midterm elections, deciding all 435 House seats and 35 Senate seats, hang over everything. History offers one comfort and one warning: the S&P 500 has risen in the year after every midterm since 1950 on some readings, averaging about 9.33 percent over twelve months in the six midterms since 2000 — but this year brings rising rates, AI-spending scepticism and recession worries that past patterns did not face in the same mix.

What the split means for investors

A market where nine sectors rise while indexes fall rewards stock-picking and punishes index-only thinking in the short term — but it also warns against celebrating breadth too early. Rotations driven by one sector's de-rating can reverse fast if the week's earnings or election results change the AI-spending story, and the same breadth that cushioned last week can narrow again just as quickly. The practical read: watch whether money keeps spreading beyond tech, whether Apple and Palantir's Monday reports steady the mega-cap narrative, and whether Friday's jobs data supports or undercuts the case for further rate cuts. Until then, the split is the signal — most stocks held up; the giants did not.

FAQ

Why did indexes fall if nine sectors rose? Because a few giant tech and semiconductor names carry outsized index weight — their losses outweighed broad gains elsewhere.

How much have AI/semiconductor leaders lost? About $5 trillion in market value since October 6, per Yahoo Finance calculations cited in weekend coverage.

What happened to Intel? Shares fell about 29 percent Friday, the steepest one-day drop since 1974, on weak Q4 guidance and a forecast 25–30 percent PC shipment fall.

What is due this week? Apple and Palantir report Monday after the close, midterms are Tuesday, AMD reports Tuesday, and October jobs data lands Friday.

Has the market always risen after midterms? The S&P 500 averaged a 9.33 percent gain in the year after the six midterms since 2000 — a historical pattern, not a guarantee.

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This article is market news and general information only, not financial advice.