Market Structure · 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 2026-09-14 · 17 ratios live
Related Beta Instability — the up/down-beta read on the same pairs →
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 (3624 names, incl. international + AI): 56% above 200d, median +6.9% YTD.
Headline check — S&P 500 above a rising 50-day average, Nasdaq-100 not above a rising 50-day average. Participation is NOT confirming the indices — hidden weakness.
Participation is contracting across multiple breadth proxies — the market may be shifting from broad advance to narrow leadership or distribution.
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 | failed recovery | -1.3% | -0.8% | -1.8% | -0.33 | 37 | -5.2% | 136 |
| QQQE/QQQ★Nasdaq-100 Equal-Weight Breadth | failed recovery | -2.3% | +0.4% | -1.7% | -0.23 | 37 | -4.7% | 32 |
| QNXT/QTOP★Nasdaq Ex-Top-30 Breadth | strong narrowing | -4.5% | -1.2% | -7.3% | -1.30 | 11 | -10.1% | 236 |
| XMAG/SPY★Ex-Mag-7 Breadth | failed recovery | -1.5% | -2.2% | -0.7% | -0.09 | 52 | -4.5% | 54 |
| SPXT/SPYEx-Tech S&P Breadth | moderate narrowing | +0.2% | -0.2% | -5.1% | -1.27 | 12 | -7.6% | 136 |
| QQXT/QQQNasdaq Ex-Tech Breadth | moderate narrowing | -1.7% | +2.1% | -16.6% | -1.20 | 20 | -19.1% | 115 |
| IWM/SPY★Small-Cap Breadth | moderate narrowing | -3.0% | -4.2% | +3.3% | -0.05 | 43 | -8.0% | 54 |
| MDY/SPYMid-Cap Breadth | strong narrowing | -3.8% | -5.5% | -4.3% | -1.25 | 10 | -7.9% | 135 |
| VXF/SPYExtended-Market Breadth | failed recovery | -3.1% | -3.1% | -2.8% | -0.68 | 25 | -6.1% | 54 |
| IWC/IWMMicro-Cap Breadth | strong broadening | +0.8% | +2.5% | +8.6% | +1.39 | 95 | -1.1% | 51 |
| HYG/LQD★Credit Breadth | strong broadening | +0.7% | +3.0% | +5.6% | +2.22 | 99 | -0.1% | 1 |
| SPHB/SPLV★High-Beta Breadth | moderate narrowing | -2.7% | -3.4% | +30.5% | +1.06 | 77 | -9.8% | 58 |
| XLY/XLPConsumer Risk Breadth | strong narrowing | -2.9% | -2.1% | -11.0% | -1.15 | 11 | -17.7% | 215 |
| XLI/XLUCyclical Breadth | failed recovery | -3.7% | +2.3% | +11.5% | +1.20 | 89 | -5.1% | 24 |
| KBE/XLUFinancial Risk Breadth | strong broadening | +0.5% | +8.3% | +12.9% | +1.82 | 100 | +0.0% | 0 |
| IWO/IWNSmall Growth Breadth | strong narrowing | -3.8% | -4.6% | -7.4% | -1.60 | 4 | -11.5% | 216 |
| IWF/IWDLarge Growth vs Value | strong narrowing | -2.2% | -5.7% | -16.6% | -1.50 | 5 | -21.6% | 218 |
| Ratio | State | 21d | 63d | 252d | z-252 | %ile-252 |
|---|---|---|---|---|---|---|
| QTEC/QQXTNasdaq Tech vs Ex-Tech | moderate narrowing | -1.7% | -4.7% | +37.9% | +1.20 | 81 |
| SMH/XLKSemiconductor Leadership | moderate narrowing | -4.9% | -12.5% | +30.8% | +0.32 | 55 |
| IGV/XLKSoftware Participation | moderate broadening | +3.9% | +17.8% | -30.6% | -0.40 | 44 |
| FDN/XLKInternet Participation | moderate broadening | +2.6% | +10.9% | -24.4% | -0.68 | 34 |
| AIQ/XLKAI Participation | moderate broadening | +1.7% | -0.7% | -1.5% | -0.87 | 18 |
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 2026-09-14
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.
As of 2026-09-14, the S&P 500 breadth verdict is "Narrow-to-mixed" — 60% of names are above their 200-day average and the median stock is +8.5% year-to-date.
As of 2026-09-14, the Breadth-of-Breadth Score is 27 out of 100, reading as "Breadth deterioration".
As of 2026-09-14, the diffusion index tracks 17 structural ratios (of which 7 are core, confirmation-weighted).