SPX still looks ok - NDX is the issue and here's whyS&P 500SP_DLY:SPXTradeSentinelNotesWhat matters SPY closed 763.25 (−1.11%). Short-term participation remains constructive: 68.58% of S&P 500 stocks above SMA20. Long-term participation is only modestly positive at 51.88% above SMA200. NYSE breadth was soft but not broken (ADV issues 0.419, ADV volume 0.423, net new highs +10). VIX rose to 19.99 and VIX/VIX3M to 0.98 — stress is rising but has not yet crossed into full stress territory. What is mostly noise The single-day decline itself. Price is still above its key SMAs and short-term participation has not collapsed. TradeSentinel takeaway SPX internals are questioning the recent advance but have not yet contradicted it. Evidence is deteriorating at the margin (rising volatility ratio + soft volume) while still holding above key participation thresholds. Process stance: evidence is no longer improving; it is flattening to slightly worsening. Lean defensive on new risk until % > SMA20 stabilizes or the volatility ratio rolls over. The tension between SPX and NDX: SPX short-term participation still constructive (~69% > SMA20); Nasdaq collapsed (~50% and heavy new lows). There's a separate post for NDX.