← REPORTS · EQUITIES · 31 October 2026
Week ending 30 Oct 2026: S&P 500 -0.6%, but most stocks rose
Data and context for education, not investment advice.
THE WEEK IN THREE LINES
- The S&P 500 fell 0.6%, but 63% of the 518 stocks we track rose and the equal-weight S&P 500 gained 0.8%: the biggest companies lagged.
- Health care (+3.1%) led the sectors and communication (−5.3%) trailed; among themes, biotech rose 4.3% and software fell 5.7%.
- 44 stocks moved more than 10%, well above a bell curve's range (15–28) and the past year's median of 28. ServiceNow, Intel, Reddit and Alnylam each fell 25–29% on their results.
IN THIS REPORT · 13 SECTIONS
The week in one number#
The S&P 500 (SPY) moved -0.6% this week. Measured against its own volatility over the past year that is a 0.3σ week, and over the last 262 weeks a move at least this large, either way, happened most weeks.
Indices and assets#
| Week | Year to date | |
|---|---|---|
| S&P 500 (SPY) | -0.6% | +11.7% |
| S&P 500 equal weight (RSP) | +0.8% | +15.3% |
| Nasdaq 100 (QQQ) | -2.0% | +12.8% |
| Russell 2000 small caps (IWM) | +1.3% | +14.2% |
| Dow Jones (DIA) | -0.8% | +8.8% |
| 20+ year Treasuries (TLT) | +0.6% | -2.8% |
| Gold (GLD) | -3.0% | -10.2% |
| VIX (volatility index, level) | 19.4 (unchanged) | — |
Sectors#
Health care led (+3.1%) and Communication lagged (-5.3%): a spread of 8.4 percentage points between the best and worst sector.
| Sector ETF | Week | 4 weeks | 13 weeks | Rank over the 13 weeks before |
|---|---|---|---|---|
| Health care (XLV) | +3.1% | +11.2% | +14.2% | 2 of 11 |
| Materials (XLB) | +2.8% | +7.9% | +5.1% | 6 of 11 |
| Utilities (XLU) | +2.0% | +9.0% | -1.4% | 10 of 11 |
| Consumer discretionary (XLY) | +2.0% | +4.9% | -0.4% | 5 of 11 |
| Industrials (XLI) | +1.7% | -1.5% | -6.7% | 11 of 11 |
| Real estate (XLRE) | +1.4% | +5.8% | -3.4% | 9 of 11 |
| Consumer staples (XLP) | +1.3% | +11.0% | +5.8% | 3 of 11 |
| Financials (XLF) | +1.1% | +5.6% | -0.4% | 7 of 11 |
| Energy (XLE) | +1.0% | +11.5% | +18.3% | 1 of 11 |
| Technology (XLK) | -2.0% | -10.2% | +2.5% | 4 of 11 |
| Communication (XLC) | -5.3% | -9.4% | -7.4% | 8 of 11 |
Health care, this week's best sector, was 2nd of 11 over the 13 weeks before; Communication, the worst, was 8th. One week's order says little on its own: the longer columns show which moves are new and which continue.
Styles and factors#
| Style ETF | Week | Against the S&P 500 | Its typical weekly gap | 4 weeks | 13 weeks |
|---|---|---|---|---|---|
| Momentum (MTUM) | -1.8% | -1.3% | ±1.2 pts | -12.0% | -5.0% |
| Value (VLUE) | +0.6% | +1.2% | ±1.1 pts | -2.9% | +2.2% |
| Quality (QUAL) | -0.1% | +0.4% | ±0.5 pts | -0.9% | +1.7% |
| Low volatility (USMV) | +0.0% | +0.5% | ±1.0 pts | +4.8% | +5.5% |
| Small caps (IWM) | +1.3% | +1.9% | ±1.1 pts | -0.8% | -3.8% |
The largest gap, set against each fund's own usual gap, was Small caps (IWM): 1.9 percentage points ahead of the S&P 500; a gap at least this wide occurred in 17 of the previous 52 weeks. It is the most unusual of the 5 funds above, picked for being unusual. Each fund holds the stocks a published rule picks for one trait; a week or two of one trait doing better says little about the next.
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Themes#
| Thematic ETF | Week | Against the S&P 500 | Its typical weekly gap | 4 weeks | 13 weeks |
|---|---|---|---|---|---|
| Biotech (XBI) | +4.3% | +4.9% | ±2.1 pts | +1.0% | +6.1% |
| Aerospace & defence (ITA) | +3.7% | +4.3% | ±1.8 pts | +0.9% | -12.4% |
| Airlines (JETS) | +3.2% | +3.7% | ±2.8 pts | -4.3% | -13.9% |
| Homebuilders (XHB) | +2.6% | +3.2% | ±2.5 pts | +4.4% | -2.1% |
| Regional banks (KRE) | -0.6% | -0.1% | ±1.9 pts | +1.7% | -4.8% |
| Semiconductors (SMH) | -0.9% | -0.3% | ±2.6 pts | -17.1% | -3.3% |
| Uranium (URA) | -1.1% | -0.6% | ±3.6 pts | -15.2% | -13.7% |
| Innovation (ARK) (ARKK) | -1.5% | -1.0% | ±2.2 pts | -10.1% | +13.3% |
| Solar (TAN) | -2.1% | -1.6% | ±2.8 pts | -8.7% | -18.5% |
| Robotics & AI (BOTZ) | -2.4% | -1.9% | ±1.8 pts | -10.6% | -8.5% |
| Cybersecurity (CIBR) | -4.8% | -4.2% | ±2.3 pts | -3.5% | +10.0% |
| Software (IGV) | -5.7% | -5.1% | ±2.8 pts | -3.8% | +10.3% |
The largest gap, set against each fund's own usual gap, was Biotech (XBI): 4.9 percentage points ahead of the S&P 500; a gap at least this wide occurred in 2 of the previous 52 weeks. It is the most unusual of the 12 funds above, picked for being unusual. Thematic funds hold a few dozen stocks from one industry, so they swing more than the index and their gaps to it are wider; set against its own usual gap, a theme's week can be told apart from its normal swing, but not from news it shares with its sector.
Sectors over time#
Do sector leaders keep leading? Comparing each 13-week period with the next, 19 times since Nov 2021 (neighbouring comparisons share a period, so these are not 19 separate tests), the 3 best sector ETFs of one period were among the next period's 3 best 28% of the time, and the 3 worst stayed among the worst 21% of the time. If the order were random, both would average about 27%; in a simulation with random orders over the same number of periods, the average landed between 19% and 35% nine times in ten. The average rank correlation between one period's returns and the next was -0.07 (0 = no relation; random orders give -0.12 to 0.11 nine times in ten). Random orders gave a top-3 share at least as high as 28% in 49% of simulations, a bottom-3 share at least as low as 21% in 16%, and a correlation at least as far from 0 in 35%: none of these is rare enough to tell apart from luck.
Under the surface#
Of the stocks in our 518-stock tracked universe, 63% rose, and 69% beat the index itself. The typical (median) stock moved +1.3%, the average (equal-weight) stock +0.7%.
The S&P 500 (-0.6%) trailed its equal-weight version (RSP, +0.8%), which gives every member the same weight, by 1.4 percentage points: the largest companies did worse than the typical member. A gap at least this wide, either way, came in 31% of the past 52 weeks (typical: 1.1 percentage points).
The spread between winners and losers (the gap between the stock at the 75th percentile and the one at the 25th) was 5.2%, wider than 58% of the past year's weeks (typical: 4.9%). 53 stocks closed at a 52-week high during the week and 18 at a 52-week low.
Stocks moved together less closely than in 65% of the past 52 weeks: the average correlation between pairs of stocks' daily returns was 0.09 (typical: 0.12; 0 would mean no linear relationship, 1 that they moved in lockstep). When stocks move together, holding more of them spreads risk less. Five days is a short window for any one pair, but the same measure is taken every week over 518 stocks, so the weeks can be compared.
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| Sector | Stocks | Median stock | Share that rose |
|---|---|---|---|
| Basic Materials | 17 | +3.1% | |
| Industrial | 82 | +2.9% | |
| Consumer, Cyclical | 57 | +2.8% | |
| Utilities | 31 | +2.2% | |
| Energy | 22 | +1.3% | |
| Financial | 95 | +1.3% | |
| Consumer, Non-cyclical | 102 | +0.4% | |
| Technology | 68 | -0.7% | |
| Communications | 44 | -2.1% |
Sector by sector, day by day. Each cell is the share of a sector's stocks that rose that day. The most one-way day was Thursday: 7 of 9 sectors had more than half their stocks rise; the most divided was Tuesday, with 5 sectors mostly up and 4 mostly down. Moves shared across sectors can be consistent with influences common to the whole market, and divided days with ones specific to industries; breadth alone cannot identify the cause. 9 sectors with at least 5 stocks are shown.
| Sector | Stocks | Median stock | Gap, 75th to 25th percentile stock | Typical gap | Wider than |
|---|---|---|---|---|---|
| Basic Materials | 17 | +3.1% | 7.3% | 5.0% | 85% of 52 past weeks |
| Technology | 68 | -0.7% | 9.5% | 7.2% | 77% of 52 past weeks |
| Industrial | 82 | +2.9% | 5.5% | 4.2% | 81% of 52 past weeks |
| Consumer, Non-cyclical | 102 | +0.4% | 4.9% | 4.3% | 81% of 52 past weeks |
| Consumer, Cyclical | 57 | +2.8% | 5.1% | 4.4% | 75% of 52 past weeks |
| Utilities | 31 | +2.2% | 1.9% | 1.7% | 62% of 52 past weeks |
| Communications | 44 | -2.1% | 6.0% | 5.7% | 60% of 52 past weeks |
| Financial | 95 | +1.3% | 3.3% | 3.3% | 52% of 52 past weeks |
| Energy | 22 | +1.3% | 3.0% | 3.5% | 33% of 52 past weeks |
How far apart stocks in the same sector ended the week. The gap between the sector's 75th and 25th percentile stock, set against the same gap for the same stocks in each past week. Basic Materials stocks were the most spread out against their usual: a gap of 7.3% against a typical 5.0%, wider than in 85% of the past 52 weeks. A wide gap means the sector's stocks went their own ways; a narrow one means they moved more alike than usual. Company announcements can widen dispersion within a sector. With 17 to 102 stocks in a sector, the gap also moves around from week to week by itself.
The luck check#
44 stocks moved more than 10% this week (21 up, 23 down), counted on our database's closes. If each stock's weekly return were an independent draw from a bell curve with its usual weekly swing, we would expect about 21.2. That is above the range this simple model gives for 90% of weeks (15 to 28), so a count this high would be unusual if the model were right. Three things can each produce it: an eventful week for single stocks; returns with fatter tails than a bell curve, which they are known to have; and stocks moving together (this week's average correlation was 0.09), which the model ignores by treating them as independent. The count alone cannot say which.
Measured against the past instead of a model: over the last 52 weeks the count was typically 28, and this week's 44 was higher than in 77% of them and lower than in 21%.
Try it yourself: ten pairs of charts, one real stock and one random walk in each. Can you beat a coin flip? Play Real or Random? →
Biggest movers#
| Gainers | Sector | Week |
|---|---|---|
| PNR | Industrial | +19.8% |
| VRT | Industrial | +19.6% |
| CVNA | Consumer, Cyclical | +18.1% |
| GEN | Communications | +17.1% |
| GPN | Consumer, Non-cyclical | +16.9% |
| Losers | Sector | Week |
|---|---|---|
| RDDT | Communications | -36.4% |
| NOW | Technology | -33.9% |
| ALNY | Consumer, Non-cyclical | -26.3% |
| FFIV | Communications | -25.7% |
| FTNT | Technology | -24.4% |
Earnings this week, after the fact#
| Company | Reported | Move | S&P 500 | Its usual move | Bigger than |
|---|---|---|---|---|---|
| NOW | Wed 28 Oct, after the close | -26.9% | -0.4% | ±4.8% | 12 of 12 past |
| ALNY | Thu 29 Oct, before the open | -25.1% | -0.4% | ±4.8% | 11 of 12 past |
| RDDT | Thu 29 Oct, after the close | -29.2% | -1.8% | ±7.5% | 9 of 10 past |
| INTC | Thu 29 Oct, after the close | -28.6% | -1.8% | ±8.9% | 12 of 12 past |
| BA | Tue 27 Oct, before the open | -10.7% | +0.6% | ±3.6% | 12 of 12 past |
| PNR | Tue 27 Oct, before the open | +12.8% | +0.6% | ±4.4% | 12 of 12 past |
| VRT | Wed 28 Oct, before the open | +16.5% | +0.3% | ±6.2% | 10 of 12 past |
| FFIV | Tue 27 Oct, after the close | -20.4% | +0.3% | ±7.9% | 12 of 12 past |
| CAT | Thu 29 Oct, before the open | -9.3% | -0.4% | ±4.0% | 10 of 12 past |
| FTNT | Wed 28 Oct, after the close | -20.1% | -0.4% | ±9.1% | 10 of 12 past |
| XOM | Fri 30 Oct, before the open | +2.2% | -1.8% | ±1.0% | 10 of 12 past |
| GOOGL | Wed 28 Oct, after the close | -12.6% | -0.4% | ±6.1% | 12 of 12 past |
These are selected, not a sample: of the 28 companies we checked that reported this week (the largest companies, those on last week's schedule and this week's biggest movers), the table shows the 12 whose moves were largest against their own usual move. Among these 12 selected earnings reactions, 12 moved more than the company's own typical earnings-day move; that says how they were picked, not how earnings go in general. A 5% move on results is ordinary for some companies and rare for others, so each move is set against the same company's past reports rather than against the market. The move includes everything else that happened on those days; the S&P 500 column is the whole market over the same days. "Its usual move" is the median size of the company's moves, up or down, on up to 12 earlier reports.
Last week's movers, one week on#
| Last week's mover | Was a | Last week | This week |
|---|---|---|---|
| HAS | gainer | +18.9% | +1.4% |
| CRL | gainer | +15.1% | +4.1% |
| ROP | gainer | +14.5% | +6.5% |
| ALLE | gainer | +14.3% | +4.2% |
| CRWD | gainer | +13.3% | -2.8% |
| FIX | loser | -19.3% | +6.2% |
| HWM | loser | -15.9% | +7.2% |
| FLEX | loser | -15.4% | +13.0% |
| PWR | loser | -13.5% | +13.6% |
| LRCX | loser | -12.8% | +3.9% |
4 of last week's 5 biggest gainers rose again this week (average +2.7%); 0 of last week's 5 biggest losers fell again this week (average +8.8%). Five names a side is far too few to say whether big weekly moves tend to continue or reverse: the record builds up week by week.
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What this week does not tell us#
- The equal-weight S&P 500 beating the cap-weighted S&P 500 means the biggest companies have clearly lost their grip. The gap was 1.4 percentage points, but 31% of past weeks had a gap at least this wide either way, and one week is too small a sample for a bigger claim.
- This was a dramatic week for the market as a whole. The S&P 500 fell 0.6%, a 0.3σ week, and 78% of past weeks moved at least this much either way: this week was smaller than most.
- 44 stocks moving more than 10% proves something exceptional about how returns are distributed. The bell-curve comparison treats stocks as independent, while real returns have fatter tails and move together. Against actual past weeks, 77% had fewer such moves and 21% had more: notable, but not enough to settle the story.
- This week's sector winners are now the ones that keep winning. The longer-run check does not support that: the top 3 sectors stayed top 3 in the next 13-week period 28% of the time, against 27% if the order were random, and the average rank correlation was −0.07. Neighbouring comparisons share a period, so the evidence is thinner than 19 comparisons suggests.
Scheduled next week#
- AAPL reports earnings on Tue 03 Nov
- PFE reports earnings on Tue 03 Nov
- AMD reports earnings on Wed 04 Nov
- AMGN reports earnings on Wed 04 Nov
- BKNG reports earnings on Wed 04 Nov
- MCD reports earnings on Wed 04 Nov
- GPN reports earnings on Thu 05 Nov
- QCOM reports earnings on Thu 05 Nov
Data: index, sector, style and thematic ETF, VIX and named-stock prices from Yahoo Finance (adjusted closes); earnings dates and times from Yahoo Finance; breadth (overall and by sector and day), dispersion (overall and within each sector), how closely stocks moved together, highs and lows and the luck check computed from unadjusted daily closes of our 518-stock tracked universe (the US stocks, drawn from S&P 500 names, that our trading database tracks, with each share class counted (FOX/FOXA, NWS/NWSA); this list is not reconciled with the index's official constituents for the week, and at 518 it is larger than the index's ~503 lines, so it includes some stocks that are not current members), published as aggregates only. Weeks run Friday close to Friday close. Not investment advice.
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