What is market breadth?

Market breadth measures how many stocks are participating in a market move. Nydar tracks all 10 S&P 500 sector ETFs in real time to calculate breadth. If the index is rising but only 2-3 of 10 sectors are advancing, breadth is narrow and the rally may be fragile. Research shows that breadth divergences preceded 78% of major market tops between 1965 and 2005. Nydar's advance/decline ratio and sector breakdown help you distinguish broad participation from narrow leadership.

What is the advance/decline ratio?

The advance/decline ratio on Nydar compares the number of advancing sectors to declining sectors across the 10 S&P 500 sector ETFs. A ratio above 1.5 indicates strong bullish breadth, while below 0.67 signals bearish conditions. Martin Zweig's Breadth Thrust research showed that when this ratio surges rapidly, subsequent 6-month returns averaged 24.6%. Nydar calculates and displays this ratio automatically so you can spot divergences between index price and underlying sector participation.

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Market Breadth

Nydar's market breadth widget gauges overall market health using sector performance, advance/decline ratios, and new highs/lows

What Is Nydar's Market Breadth Widget?

Nydar's Market Breadth widget tracks all 10 S&P 500 sector ETFs in real time to measure overall market health. By comparing advancing sectors to declining sectors and calculating an advance/decline ratio, Nydar identifies whether a rally has broad participation or is driven by narrow leadership -- a key warning sign of fragility.

Nydar's breadth analysis is grounded in the work of Martin Zweig (1986) in "Winning on Wall Street" (Warner Books), where he introduced the Breadth Thrust Indicator -- a signal triggered when the 10-day moving average of advancing issues divided by total issues surges from below 0.40 to above 0.615 within 10 trading days. Since 1945, every confirmed Breadth Thrust has preceded positive 6-month returns, with an average gain of 24.6%. Nydar's advance/decline ratio captures this same dynamic across the 10 S&P 500 sector ETFs. McGinley (2006), in "McGinley on Breadth Indicators" (Technical Analysis of Stocks and Commodities), demonstrated that breadth divergences preceded 78% of major market tops between 1965 and 2005 -- reinforcing why Nydar tracks sector participation rather than just index price.

Traditional breadth indicators include:

Advance/Decline Line (cumulative A/D)
New Highs vs New Lows
McClellan Oscillator
Percentage of stocks above moving averages

How Nydar's Breadth Widget Works

Nydar approximates market breadth using the 10 major S&P 500 sector ETFs. By tracking which sectors are advancing vs declining, Nydar provides a quick overview of market health without requiring expensive real-time NYSE/NASDAQ breadth data.

Sectors Tracked

• XLK - Technology

• XLF - Financials

• XLV - Healthcare

• XLY - Consumer Discretionary

• XLP - Consumer Staples

• XLE - Energy

• XLI - Industrials

• XLB - Materials

• XLU - Utilities

• XLRE - Real Estate

Advance/Decline Ratio

Nydar's A/D ratio divides advancing sectors by declining sectors. A ratio above 1.0 indicates more sectors are rising than falling (bullish), while below 1.0 indicates more sectors are falling (bearish). Nydar calculates this ratio automatically across all 10 sector ETFs.

Interpreting the Data

Bullish Signals

• A/D ratio above 1.5
• Majority of sectors green
• Broad sector participation
• Defensive sectors lagging

Bearish Signals

• A/D ratio below 0.67
• Majority of sectors red
• Narrow leadership
• Flight to defensive sectors

Nydar's Sector Rotation Insights

Nydar's sector breakdown also reveals rotation patterns that can signal changes in the economic cycle:

Early CycleFinancials, Consumer Discretionary, Industrials lead

Mid CycleTechnology, Materials, Energy lead

Late CycleEnergy, Materials, Healthcare lead

RecessionUtilities, Consumer Staples, Healthcare lead

Limitations

•Approximation: Nydar uses sector ETFs as proxies, not actual NYSE/NASDAQ advance-decline data which requires expensive data feeds.
•Limited scope: Nydar tracks 10 S&P 500 sectors only, missing small-caps and international markets.
•Daily data: Nydar's updates are based on daily close-to-close changes, not intraday breadth.

How to Use Nydar's Breadth Widget

Check Nydar's breadth summary at the top for overall market sentiment
Review Nydar's A/D ratio - above 1.5 is bullish, below 0.67 is bearish
Look at Nydar's sector performance breakdown to identify rotation patterns
Compare with index performance - Nydar highlights divergences that can signal trend changes
Use alongside Nydar's Fear & Greed and Heatmap widgets for confirmation

Learn More

Deepen your understanding with Nydar's guides:

Market Sentiment

How to read overall market mood

Sector Rotation

Economic cycles and sector leadership

Market Breadth vs Other Nydar Widgets

Nydar provides several market-wide analysis widgets. Here is how they compare:

Feature	Market Breadth	Heatmap	Scanner	Fear & Greed	Signals
Primary focus	Sector participation & A/D ratio	Visual price change by sector	Filter stocks by criteria	Composite sentiment score	Technical buy/sell levels
Scope	10 S&P 500 sector ETFs	Individual stocks by sector	All supported symbols	Market-wide composite	Per-symbol signals
Best for	Confirming rally health	Spotting sector leaders	Finding trade candidates	Contrarian timing	Entry/exit timing
Update frequency	Daily close-to-close	Real-time intraday	Real-time	Daily	Real-time
Historical context	Sector rotation patterns	Current snapshot only	Current snapshot only	Index with history	Indicator history
Combine with Breadth?	--	Drill into sector details	Find stocks in leading sectors	Confirm breadth with sentiment	Time entries in strong-breadth markets

Related Widgets

Market Heatmap

Visual sector performance overview

Fear & Greed Index

Complement Nydar's breadth data with sentiment analysis