# Thursday's AI-to-defensives swing was rare, not routine
Latent Equity · published Oct 23, 2026 · Market rotation
Post: https://x.com/Latent_Equity/status/2113728539119776144

Our read: Thursday's swing out of AI stocks and into defensives was rare, not routine. The Defensives/AI-stack ratio rose 9.0% in one day (our calc), the 8th-largest day of 7,015 since 1998 (99.89th pct).

What the baskets are: Defensives is an equal-weight basket of 14 holdings: 11 defensive stocks plus the $XLP, $XLU and $XLV sector funds. The Complete AI Stack is an equal-weight basket of 18 AI names, including $NVDA, $MSFT, $AMZN, $ORCL, $AMD and $TSM. AI Power (11 names) and Semis (15 names) are separate equal-weight baskets that overlap the stack. The ratio is simply one basket's value divided by the other's, so it rises when defensives beat AI.

Thursday 10/22:
- Defensives +2.83%
- AI Power -6.83%
- Semis -6.37%
- Complete AI Stack -5.70%

Big days like this cluster. 2 of the 5 biggest days have come since Jan 2025 (our calc). Over the last 20 trading days the ratio is up 21.5% (our calc).

Context: that sounds extreme, but it's a snap-back from a deep low. The ratio is still only -0.13σ vs its 1-year average (our calc), close to that average.

What would prove us wrong (our thresholds):
- Friday's close gives back half or more of Thursday's move (the ratio falls 4.5% or more). Then Thursday reads as a one-day blip, not a rare shift.
- A recheck puts Thursday below the 99th percentile on any of our three basket builds, including simple $XLP/$XLU/$XLV vs $SMH or $SOXX versions.

General research, the same for every reader. Not investment advice.