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Latest Market Anatomy

Market Anatomy, Tuesday, September 29, 2026

Published Sep 29, 2026, 4:30 PM ET

Today's move, what drove it, and what the available information cannot explain.

7,670.84 -0.17%1d

Capitalisation weighted, so a move in the largest companies moves it more than a move in the smallest.

the last 40 stored closes, scaled to their own range
26,797.54 -0.09%1d

Every Nasdaq listing, weighted by capitalisation and heavy in technology.

51,349.92 -0.26%1d

Thirty names weighted by price rather than by capitalisation, so it can disagree with the S&P for arithmetic reasons alone.

2,807.92 -0.35%1d

Small capitalisation names. Read against the S&P, it is the size half of how broad a day was.

209.50 -0.11%1d

The same five hundred companies weighted equally, so the largest names count no more than the smallest. Read against the cap-weighted index, the gap is how much of the day belonged to the biggest companies.

Cap weight against equal weight-0.05pp

The two moved together, so the session was not a story about the largest companies.

Market participation

25%

2 of 8 tracked indices above their 50-day average

Counted over ^GSPC, ^IXIC, ^DJI, ^RUT, ^FTSE, ^N225, ^GDAXI, 000001.SS. This is a reading across whole market indices, not a count of the companies inside any one of them.

Sentiment

Fear and Greed
32 -5.88%1d

CNN's own index, stored at the close. Context for whether sentiment confirms the tape or contradicts it.

16.04 -0.19%1d

Expected thirty day volatility from S&P 500 options. Rising with the index is the contradiction worth seeing.

Today's key movers

+3.91%
ORCL 137.79
NO CLEAR CATALYST

The evidence read for this company over the 7 days before the session was its own SEC filings, its stored corporate actions, the headline feed collected for its ticker and the clustered news events this system collects every two hours across every category. Rows naming this company were read inside that window and none of them was resolved to this session's move.

Moved 3.9%, at or above the 3% floor for this strip

+3.24%
META 738.79
NO CLEAR CATALYST

The evidence read for this company over the 7 days before the session was its own SEC filings, its stored corporate actions, the headline feed collected for its ticker and the clustered news events this system collects every two hours across every category. Rows naming this company were read inside that window and none of them was resolved to this session's move.

Moved 3.2%, at or above the 3% floor for this strip

+3.13%
MRNA 203.46
NO CLEAR CATALYST

The evidence read for this company over the 7 days before the session was its own SEC filings, its stored corporate actions, the headline feed collected for its ticker and the clustered news events this system collects every two hours across every category. None of them holds a row for this company inside that window.

Moved 3.1%, at or above the 3% floor for this strip

Open questions

  • What is driving Oracle?+3.91%
    The evidence read for this company over the 7 days before the session was its own SEC filings, its stored corporate actions, the headline feed collected for its ticker and the clustered news events this system collects every two hours across every category. Rows naming this company were read inside that window and none of them was resolved to this session's move.
  • What is driving Meta Platforms?+3.24%
    The evidence read for this company over the 7 days before the session was its own SEC filings, its stored corporate actions, the headline feed collected for its ticker and the clustered news events this system collects every two hours across every category. Rows naming this company were read inside that window and none of them was resolved to this session's move.
  • What is driving Moderna?+3.13%
    The evidence read for this company over the 7 days before the session was its own SEC filings, its stored corporate actions, the headline feed collected for its ticker and the clustered news events this system collects every two hours across every category. None of them holds a row for this company inside that window.

Built in code from the movers whose evidence did not resolve, so no written summary can shorten this list.

Key takeaways

  1. 1

    The S&P 500 fell 0.17% while Nasdaq fell 0.09%, Dow fell 0.26% and Russell 2000 fell 0.35%, a narrower spread across large caps and small caps than the prior session's uniform decline.

  2. 2

    Participation held at 3 of 8 tracked indices above their 50-day average, unchanged from last session, so the smaller headline move came without any shift in participation.

  3. 3

    Sector performance split, with Utilities up 1.17% against Energy down 0.90% and Materials down 0.75%, a narrower range than the prior session's Communication Services to Consumer Discretionary divide.

  4. 4

    VIX fell 0.25% while Fear and Greed fell 5.88%, the two sentiment readings moving in opposite directions rather than together as they did last session.

Sector spread

  • +1.17%
  • +0.26%
  • +0.21%
  • +0.14%
  • -0.02%
  • -0.02%
  • -0.31%
  • -0.33%
  • -0.52%
  • -0.75%
  • -0.90%

One session, from the stored closes of the eleven sector ETFs. Each bar is scaled against the widest move of the day, so the shape is the spread and not an absolute size.