Zweig Breadth Thrust: Is It Flashing Right Now?
The Zweig Breadth Thrust is Marty Zweig's rare, deeply bullish breadth signal: the 10-day average of advancing ÷ (advancing + declining) issues surging from below 0.40 to above 0.615 within 10 trading days — breadth flipping from washed-out to broad buying in two weeks. It has marked the start of durable advances. Live reading and full history in the covered history. Concepts: Zweig Breadth Thrust — definition & spec · breadth thrust, the broader idea — this page is the live gauge.
Today's reading
As of market close on October 8, 2026, no thrust is active and breadth is mid-range. Our 10-day breadth EMA is 0.46 (a thrust requires it to surge from below 0.40 to above 0.615 within 10 trading days). The last thrust fired on January 8, 2019. There have been 1 thrusts in the covered history; SPY was higher 12 months later after 1 of the 1 events with a complete forward year.
Sources, methodology & freshnessDaily advancing/declining issues from eligible US common stocks (roughly 4,750 in a typical session; available history) · Daily after US market close (~1pm PT)Data as of 2026-10-08 · Open ↓Close ↑
A thrust needs the EMA to climb from below 0.40 to above 0.615 within 10 sessions. SPY was higher 12 months later after 1 of the 1 graded thrusts in the covered history.
The S&P 500 and the breadth thrust indicator
Every thrust in the covered history — and what the S&P 500 did next
| Thrust date | Days from washout | SPY +3m | SPY +6m | SPY +12m |
|---|---|---|---|---|
| Jan 8, 2019 | 8 | +11.9% | +16.3% | +26.4% |
| Average | — | +11.9% | +16.3% | +26.4% |
Computed on our reconstructed US-listed common-share universe from 2016-11-14. Dated classifications, available live and delisted price histories, and valid consecutive traded closes determine membership. Historical coverage is incomplete. The classic thresholds were developed for NYSE issues; our broader universe can produce different signals. Forward returns use SPY closes 63 / 126 / 252 trading days after each thrust. The 1 events with a complete forward year form a small sample.
The Manual — Zweig Breadth Thrust
Our universe has completed 1 thrusts in the covered history (1 of 1 graded were higher a year later, averaging 26.4%) against 24 near-misses. The full owner's guide covers the exact state machine, the literature's 1945+ record with sources, why thrust lists disagree, and the specific ways this signal will mislead you.
Read The Zweig Breadth Thrust Manual →A thrust needs the EMA to climb from below 0.40 to above 0.615 within 10 sessions. SPY was higher 12 months later after 1 of the 1 graded thrusts in the covered history.
How Zweig Breadth Thrust Works
- 1Measure each day's advance ratioFor every session we take the number of advancing stocks divided by the number of advancing plus declining stocks. A reading of 0.50 means an even split; above 0.50, advancers outnumber decliners that day.
- 2Smooth it with a 10-day EMAThe Breadth Thrust indicator is the 10-day exponential moving average of that daily ratio. Smoothing turns the noisy daily breadth into a regime read: a low EMA means breadth has been broadly negative, a high EMA means broad, persistent buying.
- 3Watch for the surge from washed-out to broad buyingA Zweig Breadth Thrust fires when the 10-day EMA climbs from below 0.40 (deeply oversold breadth) to above 0.615 (broad buying) within 10 trading days. The speed is the point — it marks the moment a beaten-down market flips to broad, urgent accumulation.
- 4Read the live statusWe label the current reading Neutral, Armed (the EMA is below 0.40, so a thrust becomes possible if breadth surges), or Thrust fired (a thrust triggered within the last 10 sessions). The table below shows every thrust in the covered history and what the S&P 500 did in the 3, 6 and 12 months after.