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B21 Decision Desk Real money

Market breadth

How many of the 101 Nasdaq-100 names went up against how many went down, and what that is doing to the market's internals. Read only — nothing here changes what the engine does.

Latest reading

The settled record is written once, after the close.

Engine state Gate mode — Regime — Session — Read only
McClellan Oscillator
Loading the breadth record…
Summation Index
Advances / declines
Sessions in view

The Summation Index

A running total of the Oscillator: each session's Oscillator reading is added to the day before. It is a trend line, not a level to buy or sell — read its direction and where it sits against its own 10-day average. Because it is a running total, every step has to reconcile; a step that does not is a hole in the record, so the page checks all of them and says so below.

Summation Index · 10-day average

Summation Index 10-day average Zero

No fixed overbought or oversold level exists for the Summation Index. Across the stored record it averages roughly +486 with a spread of about 384, and has ranged from about −100 to about +1200, so a level means little on its own. Watch the direction and the crossing of the 10-day average. The zero line is drawn only when zero is genuinely inside the visible range.

Continuity of the record

Checking every step in view…

The Oscillator

The day's breadth pressure. It is the 19-day exponential average of net advances minus the 39-day one, so it turns before the Summation Index does. Above the bands the market has bought too hard, below them it has sold too hard.

McClellan Oscillator

Positive Negative Overbought, +60 Oversold, −60

Bands sit at ±60 — the 5th and 95th percentiles of this system's own three-year record, about 1.6 standard deviations. The classic ±100 New York Stock Exchange levels are calibrated for roughly 3,000 issues and would essentially never trigger on a 100-stock universe. The Oscillator itself uses the ratio-adjusted method, (advances − declines) ÷ (advances + declines) × 1000, which normalises for how many names are being measured.

Participation

How wide the move is. New highs against new lows says whether leadership is broadening or thinning; the share of names above their own moving average says how many are still in an uptrend at all.

Net new 52-week highs
Above the 5-day average

52-week net new highs

More highs More lows

New highs minus new lows. A name counts as a new high when its high touches the highest of the last 252 sessions, and as a new low on the same test against the lowest.

Share above a moving average

Above 5-day average Above own 21-day EMA

Overbought at 75.0% or more, oversold at 25.0% or less. Those conventional levels match this system's own 90th and 10th percentiles — 80.2% and 23.8% — almost exactly. The 21-day line is the slower read the posture layer uses: it answers how much of the universe would pass the engine's own trend filter right now. It is stored only for the most recent 90 sessions.

Volatility and selling pressure

What the options market is paying for protection, and how hard institutions have been selling. These four columns are stored only for the most recent 90 sessions, and nine of those sessions have no VIX at all. Where a value is missing it is shown as an em dash and the line breaks — it is never drawn as a zero and never bridged.

VIX
VIX 3-month
Term structure
Distribution days

VIX against 3-month VIX

VIX VIX 3-month

Term structure, VIX ÷ 3-month

VIX ÷ 3-month VIX Parity, 1.00

Below 1.00 the market is charging more for protection three months out than for protection now, which is the calm arrangement. At or above 1.00 that has flipped: near-term fear is being priced above longer-term fear. The reading is simply today's VIX divided by the three-month VIX.

Distribution days, trailing 25 sessions

Days counted

A distribution day is a session where the equal-weight Nasdaq-100 fell more than 0.20% on higher volume than the day before — large sellers leaving while the price still looks fine. The count is over the last 25 sessions. It is stored only for the most recent 90 sessions.

The record

Every stored column for every session in view, newest first. Nothing is hidden on a narrow screen; the table scrolls sideways with the date pinned.

Scrolls sideways — 20 columns
The stored breadth record, newest first.
Date Row Adv Dec Net A/D MCO MCSI MCSI 10-avg Gap New highs New lows Net H/L > 5-day (%) > 21 EMA (%) Dist days VIX VIX 3M VIX / 3M Index stretch Weekly
Loading the breadth record…
before 90 sessions ago — the extended columns are stored only for the most recent 90 sessions. inside that window — the value was not recorded for that session.
Adv / Dec how many names closed up, and how many closed down Net A/D advances minus declines, scaled to 1000 so the reading does not depend on how many names were measured MCO McClellan Oscillator: the 19-day average of Net A/D minus the 39-day average of it MCSI Summation Index: every Oscillator reading added to the one before it MCSI 10-avg the Summation Index averaged over its own last 10 sessions Gap the Summation Index minus that 10-session average New highs/lows names whose high touched the highest of the last 252 sessions, or whose low touched the lowest Net H/L new highs minus new lows > 5-day the share of names trading above the average of their own last 5 closes > 21 EMA the share of names trading above their own 21-day exponential average Dist days sessions in the last 25 where the equal-weight Nasdaq-100 fell more than 0.20% on higher volume than the day before VIX / VIX 3M what the options market charges for one month of protection, and for three months VIX / 3M the first divided by the second: at or above 1.00, near-term fear is priced above longer-term fear Index stretch how far the equal-weight Nasdaq-100 sits from its own average, in standard deviations Weekly whether the weekly price structure is intact or broken