Market Breadth: How I Read The Index With NDTW, NDFI, NDTH And The Finviz Bubble Chart

The index can rise while most stocks weaken. Here are the two tools I use to get situational awareness of what is really happening underneath the number.

Introduction

Let me start with the part most retail traders never check. The index closes green, and you assume it was a good day. Often it was not. Most of the stocks underneath were red.

This happens because the index is weighted by size. A handful of mega caps can carry the whole thing higher while the average stock quietly weakens. The headline closes up, the media calls it a strong day, and the damage underneath goes unseen. If you only watch the index print, you are watching a story. Not the market.

So I do not just watch the print. I use two tools to see what is happening underneath it. Market breadth indicators tell me whether the index is healthy. The Finviz intraday bubble chart shows me how the move is built, which names and which market cap sizes are doing the work. Neither tells me what to buy. Together they tell me what kind of market I am standing in.

Think of the index as the scoreboard and breadth as the game. You do not bet on the next play by staring at the scoreboard. You watch the field. Narrow rallies are the ones that hurt. The index grinds higher on five or six names, retail assumes the rising tide is lifting everything, and they buy the broken stuff that is not participating.

Then the leaders roll over, there is nothing underneath to catch the tape, and it gaps down. The people watching the scoreboard never saw it coming. The people reading breadth had been getting defensive for weeks.

Strength not noise. That is the filter.

Tool one: the market breadth indicators I watch

For the Nasdaq 100 I read participation across three timeframes. Short, intermediate, and long. Each one is the percentage of Nasdaq 100 stocks trading above a given moving average.

NDTW is the short term gauge. It is the percentage of Nasdaq 100 stocks above their 20 day moving average. This one moves fast. It tells me what is happening right now, this week, on a tactical basis.

NDFI is the intermediate gauge. It is the percentage of Nasdaq 100 stocks above their 50 day moving average. This is the swing timeframe and the one I weight most for positioning over the next few weeks.

NDTH is the long term gauge. It is the percentage of Nasdaq 100 stocks above their 200 day moving average. This is the structural health of the market. When NDTH is strong, the broad trend is intact regardless of short term chop.

Market Breadth indicators are a great tool to get a broader understanding of the market.

I am not using these to time entries or pick names. I am using them for situational awareness.

One question. Is participation broadening or weakening.

When NDTW, NDFI and NDTH are all rising together, the market is broadening. Participation is improving from the short term right through to the structural. That is a healthy tape. When the index pushes to new highs but NDFI and NDTH are trending lower, that is the warning. The index is being carried by fewer and fewer names while the broad market weakens beneath it. Narrowing leadership. That is exactly the setup that ends in a sharp correction, because once the few leaders roll over there is nothing left holding the tape up.

The order they move in matters too. Coming out of a low, NDTW turns up first because it is the fastest. If NDFI then follows and improves faster than NDTH, that is early cycle momentum rebuilding from the short end outward.

Tool two: the Finviz intraday bubble chart

Breadth tells me whether the market is healthy. The Finviz intraday bubble chart tells me how today's move is actually being built.

If you have not used it, the layout is simple. Each bubble is a stock. The horizontal axis groups them by sector. The vertical axis is the percentage change on the day. And the size of the bubble is the market cap. So in one screen you can see what is green, what is red, how big the movers are, and which sectors they sit in.

This is where the index number gets exposed in real time. When the tape is healthy, you see a sea of green spread fairly evenly across most sectors, with the moves shared between large and small bubbles. When it is not healthy, you see something very different. A few enormous bubbles dragging their sector higher while everything around them is flat or red. That is a narrow move wearing a green index as a disguise.

Take a tech tape as the example. You might see the index up on the day, but when you open the bubble chart the technology cluster is split. One mega cap printing a strong gain, another mega cap of similar size selling off, and the giant names sitting heavy and barely moving while only the smaller bubbles are green. That is not a healthy rally. That is dispersion. The index is being propped by one or two names and the size of those bubbles is doing all the work.

That is the value of it. The breadth indicators tell me participation is thinning. The bubble chart shows me exactly where the thinning is, which mega caps are carrying the load, and whether the move is broad or concentrated by market cap. One gives me the read. The other gives me the picture.

This is the Finviz intraday bubble chart. I use it to see how the index move is actually built, which names and which market cap sizes are driving it, so a green print does not fool me into thinking the move is broad.

Putting the two together

This is the part most retail traders get wrong. They want these tools to tell them what to buy. That is not what they are for.

Neither breadth nor the bubble chart picks stocks. They give me situational awareness. They tell me what kind of market I am in, which tells me how aggressive that market deserves me to be.

Broad participation on the indicators and a wide spread of green across the bubble chart means a healthy tape. I can carry more exposure and lean into my best ideas. Thinning breadth and a bubble chart dominated by a few mega caps means a narrow tape. I size down, get selective, and stop forcing trades into a move that only a handful of names are actually making. Same setups, different environment, completely different base rate of success.

Process not prediction. I am not forecasting the next move. I am reading the environment and adjusting my behaviour to match it.

Situational awareness over stock tips

Think of it like driving in fog. You do not drive the same way in clear conditions as you do when visibility drops to nothing. Breadth and the bubble chart are my visibility gauges. When they deteriorate I slow down, tighten up, and stop forcing trades into the murk. When they clear I can put my foot down. Same road, completely different way of driving it.

I will be blunt about the trap, because I fell into it for years. The trap is anchoring on the index print because it is the number everyone quotes. It feels like the market. It is not the market. It is one weighted summary of the market, and the weighting is exactly what hides the damage when leadership narrows. The day you stop letting that single number set your mood is the day you start seeing what is really happening underneath.

Why this approach works

None of this requires you to predict anything. That is why I trust it. Prediction is fragile. Reading the environment and adjusting to it is durable.

Less noise leads to clarity. Clarity leads to better positioning. Better positioning leads to results.

You are not chasing the index. You are reading the market underneath it. And once you have watched NDFI and NDTH roll over while the index made a new high, or opened a bubble chart and seen one giant green bubble propping up a sea of red, you cannot unsee it.

Key Takeaways

• The index is a weighted average and can rise while most stocks weaken.

• NDTW, NDFI and NDTH track participation across the 20, 50 and 200 day.

• The Finviz intraday bubble chart shows which names and market cap sizes drive the move.

• Read together, the two give situational awareness, not stock picks.

• Read the environment first. Decide how aggressive to be second.

Final Thoughts

The market will keep handing you one tidy index print every day and inviting you to feel something about it. Do not take the bait. Check whether breadth is broadening or weakening, open the bubble chart to see how the move is built, then decide how hard to drive. That habit alone separates traders who get surprised from traders who were already positioned.

Strength not noise. That is the whole job.

Frequently Asked Questions

What are NDTW, NDFI and NDTH?

They are Nasdaq 100 breadth indices. NDTW is the percentage of Nasdaq 100 stocks above their 20 day moving average, NDFI is the percentage above their 50 day, and NDTH is the percentage above their 200 day. They measure short, intermediate, and long term participation.

What is the Finviz bubble chart and why use it?

It is an intraday view where each bubble is a stock, grouped by sector, plotted by percentage change on the day, and sized by market cap. It lets you see at a glance whether a move is broad or concentrated in a few large names, which the index number alone will never show you.

Why does the index rise when most stocks weaken?

The index is weighted by size, so a few very large companies can pull the headline number up even while the majority of names decline. Watching breadth and the bubble chart against the index price exposes that split.

Does any of this tell me which stock to buy?

No. These tools give you situational awareness of the environment, which tells you how aggressive to be. Stock selection is a separate step that comes after you have read the market.

Is this taught in PTM 2.0?

The broader framework of market structure and situational awareness that these tools sit inside is exactly what the ITPM material covers. You can read my full reviews and use code ptmcutts30pct for a discount on PTM 2.0.

Disclaimer

The information contained in this article is provided for general informational and educational purposes only and does not constitute financial, investment, or other professional advice. The content reflects the personal opinions of the author based on publicly available information at the time of writing and should not be relied upon as the basis for any investment decisions. Earnings reviews may contain forward-looking statements that are inherently uncertain and subject to change.

Readers are strongly encouraged to conduct their own research and due diligence, and to consult with a qualified financial advisor or licensed professional before making any investment or trading decisions. The author and publisher make no representations or warranties, express or implied, as to the accuracy, completeness, or reliability of the information provided and accept no liability for any loss or damage arising directly or indirectly from the use of or reliance on the information herein.