Learn · The Twelve Measurements — Lesson 6 of 12

Sector rotation, explained

A stock up 5% sounds strong — until you notice its sector is up 8%. Rotation is the measurement that keeps asking the awkward question: is this company leading its peers, or being dragged along behind them?

What it measures

Compares the name against its sector ETF over a month, which separates a company-specific move from a sector-wide one. A stock up 5% while its sector is up 8% is being left behind, not leading.

The comparison runs over a month, against the sector's own ETF, so the answer reflects a real, investable benchmark rather than an abstract index. The distinction it draws is between company-specific strength — the name outrunning its peers on its own merits — and sector weather, where a rising tide lifts every boat in the harbour regardless of seaworthiness.

Why it moves prices

Large pools of capital allocate top-down: decide the sector weights first, pick names second. When that money rotates — out of defensives into technology, out of growth into energy — every stock in the affected sectors moves for reasons that have nothing to do with any individual company. On a single-name chart, sector flows and company news are indistinguishable. Relative strength against the sector strips the weather out and leaves the company-specific residue, which is often the part a self-directed investor actually wants to understand.

How to read it

Positive: outperforming its sector. Negative: lagging it.

The four combinations carry different information: outperforming a rising sector (leadership), lagging a rising sector (being carried), outperforming a falling sector (relative resilience), lagging a falling sector (weakness compounding weakness). The same +2% week can be any of the four.

How Farlens uses it

Sector rotation carries 7.8% of the Farlens composite (weight 0.9 of 11.6 across all twelve measurements). Coverage: US equities with a mapped sector ETF. Not applicable to crypto or indices.

Two conventions matter here. First, a measurement that cannot be observed for an instrument is skipped, never counted as zero — a zero would read as “neutral” and quietly dilute the composite. Second, on any given day a contribution is the measurement's score times its weight, divided by the total weight of the measurements present that day — so the published breakdown always sums to the score beside it. The full stack, with every weight published, is on the signals page.

A worked example

Farlens publishes one frozen example reading — AAPL on 22 July 2026, deliberately weeks old — so the shape of a reading can be studied without opening the live layer. That day the composite printed +14.7, “Mixed”, and this measurement read −45.3.

Measurement present that day	Reading
Trend	+100.0
Advance/decline pressure	+100.0
On-Balance Volume	+97.4
Momentum (RSI)	−75.7
Money Flow Index	−63.3
Sector rotation	−45.3
Volume surge	−29.7
Short volume share	−23.9

Rotation read −45.3 that day: over the prior month the stock had been lagging its own sector even while its long-run trend stayed intact — a leadership question mark that a price chart alone would not have surfaced.

A real reading, kept deliberately stale. Descriptive of one historical day — not a prediction, and not representative of current conditions.

What it cannot tell you

Rotation inherits its benchmark's blind spots: a mega-cap can be most of its sector ETF, at which point comparing the two approaches tautology. A month window catches durable rotation but misses week-scale flows. And a lag can mean the stock is weak — or that it rallied first and the sector is catching up. The measurement flags the divergence; it cannot adjudicate the cause.

Frequently asked

What does “rotation” mean in market commentary?

Capital moving between sectors as the macro picture shifts — the classic cycle narrative runs from early-cycle sectors like financials toward defensives late in the cycle. This measurement reads each stock's position in whatever rotation is currently underway.

Why isn't this computed for crypto?

It needs a mapped sector benchmark, and crypto assets don't have sector ETFs in the same sense. Crypto names carry their own exclusive measurements instead — derivatives positioning and the 200-week average.

Is relative strength the same as RSI?

No, despite the confusing shared words. RSI compares an asset to its own recent history; relative strength compares it to something else — here, its sector.