One calibrated number, refreshed each trading morning: the probability that the S&P 500 is in a sector-rotation regime right now — and how to use it without over-reading it.
The top of the dashboard shows two probabilities between 0 and 1, side by side — one across the 11 GICS sectors, one across the industries beneath them. Each is the model's estimate that the market is currently in a rotation regime at that grain, using only data available through the as-of date. Both are detection readings (where are we now), not forecasts of what happens next.
"Rotation" here means leadership is reordering broadly — not the whole market rising or falling together, and not one mega-cap dragging its group along. Both of those are removed before the model ever sees the data (see Methodology).
Why both grains? The 11 sectors are coarse: a rotation can tear through one industry while the sector it sits in barely moves. The industry model is the full parallel of the sector model — same ruler, same filtered hidden-state machinery, same calibration and sealed-holdout validation, with its own honest AUCs shown on its card — so it is a genuine peer reading, not a derived proxy. Because it is finer, it often turns first.
The probability maps to a plain-language state:
| State | Probability | What it means |
|---|---|---|
| Calm | 0.00 – 0.20 | No active rotation. Sector leadership is stable; dispersion sits below episode thresholds. |
| Elevated | 0.20 – 0.40 | Pressure building. Dispersion rising and leadership starting to reorder — watch, don't act. |
| Rotation | 0.40 + | Active regime. Leadership reordering broadly, on breadth rather than a single name. |
These are display bands on a calibrated probability — when the model reads 0.30, rotation regimes have historically occurred about 30% of the time at that level (calibration error on the sealed test is 0.0041, essentially perfect).
Each sector's bar is its market-denoised residual return — the sector's move after removing its own beta to the index. What remains is genuine relative movement, not the market carrying everyone together. Positive (green) leads; negative (red) lags.
Breadth — the share of a sector's members actually participating — is the honesty check on each bar. A sector "leading" on thin breadth is usually one or two names, not a real rotation into it.
A single day's probability is noisy. The trend chart plots the last ~6 months of daily readings for both grains, with a 10-day trend line drawn through the day-to-day noise. The point is separation: a genuine early-stage rotation shows up as the trend line climbing toward the Elevated band, while noise stays flat and choppy.
Watch the two lines together. Because industries are one grain finer, the teal (industry) line usually lifts first; the blue (sector) line follows once the move is broad enough to show at the coarser grain. That lead time — teal rising while blue is still calm — is the window an early move lives in. The badges above the chart read off each line's direction over the last 10 sessions.
The map lays out every industry as a tile, so you can see where the rotation is concentrated at a glance — something the two headline numbers can't show.
Put together: a big green tile is an established rotation into that industry (broad and weeks-long — possibly already late); a small, vividly-coloured tile is a fresh move just beginning — the early signal. An industry drifting with the market (no real trend) stays small and neutral, so it never dominates the map by size alone.
The chart is the monthly probability since 1990, and every point uses only data available at the time — no look-ahead. Shaded months are model-flagged rotation episodes. The dashed line marks 2021: everything to its right is the sealed holdout the model was never fit on, so you can see how it behaves on data it never saw. The 2000 unwind, 2008, the 2020 shock, and the 2022 growth-to-value turn all read straight off it.
A latent-state model will fit something to any data, so the numbers below the chart are how you know this one is real:
It's a detector, not a crystal ball. Identifying whether we're in a rotation today is where the model is strong. Predicting one before it is visible is much harder, and we report that skill honestly as modest and short-lived. Don't read today's number as a forecast.
Research and educational content only — not investment advice, and not a recommendation to buy or sell any security. The reading is a statistical estimate with uncertainty.
The dashboard refreshes each trading morning (around 06:30 ET, Tuesday–Saturday), after the prior session's prices land. The "as of" date at the top always tells you the last data the reading is built on. If the price feed stalls, the page holds the last good date rather than showing a stale number dressed up as fresh.
