On a day when the S&P 500 rises, the natural question is whether the market is getting healthier. But an index can move higher while a surprising number of its stocks are falling. Market breadth begins with a more revealing question: how many stocks are helping create the move?
The number at the top is only the headline
An index gives you an average. Breadth shows you the crowd behind that average. If 80% of stocks are above their 200-day moving averages, the longer-term move has a lot of company. If only 30% are above it, the index may still be rising, but fewer names are carrying the weight.
The question beneath the question
The 200-day moving average is a slowly moving reference line based on an asset's recent closing prices. A stock above its line is trading above its recent long-term average. A stock below it is trading beneath that average. The line does not explain everything about a company. It gives you a consistent way to ask whether recent price is holding above or below a longer market memory.
A small example with a big distinction
If 250 of 500 tracked stocks are above their 200-day moving average, breadth is 50%. That number says participation is evenly split. It does not say what the index will do tomorrow. Description comes first; prediction is a separate, much harder question.
How tradingtwohundred counts it
tradingtwohundred reports an equal-weighted percentage across the tracked S&P 500 members. It is not the same thing as the index's market-cap-weighted return, and it is not real-time: the site reflects the most recent completed US trading session. See the full data and methodology page for the boundaries of each reading. For the underlying moving-average idea, see what the 200-day moving average measures.
How to use the number
A single reading is a snapshot. The useful part is the sequence around it. Compare today with the recent history, watch whether participation is expanding or weakening, and check whether sectors are moving together. The number becomes more useful when you know where it came from and what is changing underneath it.
The market dashboard shows the latest S&P 500 reading, sector participation, and longer history. Once the basic idea is clear, continue with how to read the dashboard.
What breadth cannot tell you
Breadth cannot identify the perfect entry point or predict the next day. It can remain weak while prices recover, or stay strong while prices eventually turn lower. Its value is more modest, and more durable: it makes participation visible when the index headline is telling only one part of the story.
The takeaway
Price tells you what the index did. Breadth asks how many stocks were involved. That second question will not remove uncertainty, but it can make the first answer harder to misunderstand.
Disclaimer: Data is provided for informational purposes only and is not intended as investment advice. Always do your own research before making investment decisions. We are not responsible for any losses incurred from using this information.
