Market Structure · Breadth-of-Breadth
Breadth-of-Breadth
How broad is the bull? We read it two ways. First the absolute tape — of the ~500 S&P 500 names, how many are above their moving averages, making new highs vs lows, positive on the year. Then a relative-ratio diffusion index across 17 structural proxies for the rotation underneath. Together they catch a narrow bull while the index still looks fine.
Updated daily · data as of 2026-08-26 · 17 ratios live
Related Beta Instability — the up/down-beta read on the same pairs →
Broad-market participation (S&P 500, stock-level)
The relative ratios further down read rotation; this reads the tape directly — of the ~500 S&P 500 names, how many actually participate. A bull can be narrow even with the index near highs.
MA chips = price above its 20/50/200-day average. Green-200 but red-20 = a leader rolling over; green across = a laggard firming — that's the rotation. Our full universe (2753 names, incl. international + AI): 66% above 200d, median +8.9% YTD.
Rotation & concentration (relative-ratio diffusion)
Headline check — S&P 500 above a rising 50-day average, Nasdaq-100 not above a rising 50-day average. Participation broadly tracks the indices.
Participation grid
Breadth ratios — full detail
Every structural proxy, decomposed. State classifies each ratio's participation trend; the diffusion index weights them by importance. Core ratios (★) drive the confirmation score.
| Ratio | State | 21d | 63d | 252d | z-252 | %ile-252 | DD-252 | d/high |
|---|---|---|---|---|---|---|---|---|
| RSP/SPY★S&P 500 Equal-Weight Breadth | moderate broadening | -1.3% | +5.0% | -0.4% | +0.87 | 79 | -2.7% | 124 |
| QQQE/QQQ★Nasdaq-100 Equal-Weight Breadth | moderate broadening | -0.3% | +6.9% | +0.1% | +1.61 | 97 | -1.5% | 20 |
| QNXT/QTOP★Nasdaq Ex-Top-30 Breadth | strong broadening | +0.7% | +11.6% | -0.0% | +0.82 | 80 | -3.0% | 224 |
| XMAG/SPY★Ex-Mag-7 Breadth | moderate narrowing | -0.6% | +2.8% | +1.3% | +1.08 | 83 | -2.9% | 42 |
| SPXT/SPYEx-Tech S&P Breadth | moderate broadening | -1.4% | +1.4% | -4.3% | -0.94 | 25 | -6.5% | 124 |
| QQXT/QQQNasdaq Ex-Tech Breadth | moderate broadening | -2.2% | +8.3% | -14.8% | -0.71 | 29 | -15.3% | 103 |
| IWM/SPY★Small-Cap Breadth | moderate narrowing | -1.5% | +0.8% | +7.8% | +0.94 | 80 | -5.1% | 42 |
| MDY/SPYMid-Cap Breadth | moderate narrowing | -2.5% | +0.8% | -0.8% | -0.11 | 42 | -5.0% | 123 |
| VXF/SPYExtended-Market Breadth | moderate narrowing | -0.5% | +2.3% | +0.7% | +0.68 | 77 | -3.8% | 42 |
| IWC/IWMMicro-Cap Breadth | moderate broadening | +2.2% | -0.2% | +8.6% | +1.21 | 92 | -1.5% | 39 |
| HYG/LQD★Credit Breadth | strong broadening | +0.7% | +2.0% | +3.3% | +2.05 | 96 | -0.7% | 7 |
| SPHB/SPLV★High-Beta Breadth | moderate broadening | +9.8% | -1.8% | +36.1% | +1.29 | 87 | -8.7% | 46 |
| XLY/XLPConsumer Risk Breadth | moderate narrowing | +5.1% | -6.0% | -7.2% | -0.98 | 21 | -16.4% | 203 |
| XLI/XLUCyclical Breadth | strong broadening | +3.4% | +6.9% | +14.6% | +1.66 | 95 | -3.2% | 12 |
| KBE/XLUFinancial Risk Breadth | strong broadening | +2.2% | +11.9% | +10.9% | +1.56 | 94 | -2.9% | 15 |
| IWO/IWNSmall Growth Breadth | recovery attempt | +3.5% | -3.1% | -4.0% | -0.80 | 27 | -8.8% | 204 |
| IWF/IWDLarge Growth vs Value | moderate narrowing | +1.9% | -11.1% | -16.1% | -1.78 | 3 | -22.3% | 206 |
Tech-internal leadership (measured separately — concentration, not market breadth)
| Ratio | State | 21d | 63d | 252d | z-252 | %ile-252 |
|---|---|---|---|---|---|---|
| QTEC/QQXTNasdaq Tech vs Ex-Tech | moderate narrowing | +4.3% | -4.1% | +37.8% | +1.12 | 75 |
| SMH/XLKSemiconductor Leadership | moderate narrowing | -1.8% | -6.0% | +35.1% | +0.67 | 66 |
| IGV/XLKSoftware Participation | moderate broadening | +4.4% | +10.9% | -31.6% | -0.66 | 37 |
| FDN/XLKInternet Participation | moderate broadening | +0.5% | +5.8% | -24.7% | -0.83 | 29 |
| AIQ/XLKAI Participation | moderate broadening | +3.1% | -2.4% | +0.4% | -0.83 | 18 |
How to read it
Each ratio (numerator ÷ denominator, adjusted close) gets a full work-up — trend vs its 20/50/100/200-day averages, momentum over 5/21/63/126/252 days, a log z-score, percentile rank and relative drawdown — and is classified into a participation state. The diffusion index weights each ratio's state by importance; the composite score (0–100) blends the share above their 50-day average, the share with positive quarterly momentum, the diffusion, the median z and the core-ratio confirmation. Hidden breadth weakness fires when SPY/QQQ are positive but the score is weak — participation not confirming the tape.
For information and discussion only — a reading of market internals, not investment advice. Scores are relative and descriptive, on uncalibrated thresholds. Cross-read with Beta Instability, the Money Temperature regime and Cointegration.
FAQ · from the current data · as of 2026-08-26
Quick answers
What does Breadth-of-Breadth measure?
It reads participation two ways: the absolute tape (of the roughly 500 S&P 500 names, how many are above their moving averages, making new highs vs lows, positive on the year) and a relative-ratio diffusion index across roughly 16 structural proxies for the rotation underneath. Together they catch a narrow bull even while the index looks fine.
What is the current breadth verdict for the S&P 500?
As of 2026-08-26, the S&P 500 breadth verdict is "Broad" — 73% of names are above their 200-day average and the median stock is +10.8% year-to-date.
What is the Breadth-of-Breadth Score right now?
As of 2026-08-26, the Breadth-of-Breadth Score is 62 out of 100, reading as "Mixed participation".
How many structural ratios does Breadth-of-Breadth track?
As of 2026-08-26, the diffusion index tracks 17 structural ratios (of which 7 are core, confirmation-weighted).