Published Oct 6, 2026, 4:37 PM ET
Today's move, what drove it, and what the available information cannot explain.
Capitalisation weighted, so a move in the largest companies moves it more than a move in the smallest.
Every Nasdaq listing, weighted by capitalisation and heavy in technology.
Thirty names weighted by price rather than by capitalisation, so it can disagree with the S&P for arithmetic reasons alone.
Small capitalisation names. Read against the S&P, it is the size half of how broad a day was.
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.
The two moved together, so the session was not a story about the largest companies.
38%
3 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.
CNN's own index, stored at the close. Context for whether sentiment confirms the tape or contradicts it.
Expected thirty day volatility from S&P 500 options. Rising with the index is the contradiction worth seeing.
Google nuclear power deal with Constellation Energy announced same day as the 12.2% jump.
News event dated 2026-10-06, MarketWatch Top Stories: Google signs major nuclear power deal with Constellation Energy to fuel AI data center expansion
Moved 12.2%, at or above the 3% floor for this strip
Report of Musk hinting TSMC may join rival chip venture coincided with Intel's 3.2% decline.
News event dated 2026-10-06, MarketWatch Top Stories: Intel stock slips as Musk hints TSMC may join Terafab chip venture
Moved 3.2%, at or above the 3% floor for this strip
Headline cites AMD hitting a record high on a price target hike the same day.
Headline dated 2026-10-06: Advanced Micro Devices Stock Hits Record High on PT Hike - Schaeffer's Investment Research
The third largest one-session move among the 61 companies this system prices daily
Every mover above resolved to a stored filing, headline or news event today, so there are no open questions.
Participation held at 3 of 8 tracked indices above their 50-day average even as the S&P 500 rose 0.58%, matching the same reading from the prior session.
The gap between the headline index move of 0.58% and the equal weight fund move of 0.57% was just 0.01 points, little changed from the prior session's 0.00 point gap.
The Russell 2000 fell 0.59% while the S&P 500, Nasdaq, and Dow all rose, a divergence not present in the prior session's broader index agreement.
Sector returns spanned Utilities up 2.98% to Health Care down 0.17%, a wider dispersion than the prior session's range from 1.31% to negative 0.34%.
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.