Introduction
Here’s a riddle: the S&P 500 is trading just shy of record territory, yet most individual stocks are struggling. Small and midcap indexes have sold off hard, many big-company stocks are down 10% or more from their highs, and the average stock is quietly sitting in a correction. How can the market look fine from the outside and terrible from the inside? The answer is called “bad breadth” — and it matters more for your money than the headline number ever will.
Table of Contents
- – What “Bad Breadth” Actually Means
- – Why Tech Is Carrying the Whole Market
- – What This Means for Your Portfolio
- – What Should You Do About It
- – The Bottom Line
What “Bad Breadth” Actually Means
The S&P 500 is weighted by market value, which means the biggest companies — the tech giants — pull most of the weight. When a handful of mega-cap stocks rise, they can drag the entire index upward even while hundreds of other stocks fall. Compare the regular S&P 500 to its equal-weighted sibling (which treats every company the same), and the difference is stark: the gap between the two has reached one of its widest levels on record going back to the early 2000s, according to Dow Jones Market Data.
The numbers tell the story. During September, the S&P 500 eked out only a modest loss for the month — but technology was the only sector to finish higher. The equal-weighted version of the index was trading about 6% below a record high reached last month. The Invesco S&P 500 Equal Weight ETF, which tracks it, moved higher on Thursday but remained on track to log a seventh straight week in the red. That’s the median stock in the index, in decline, for seven straight weeks.
Why Tech Is Carrying the Whole Market
A few names are doing nearly all the heavy lifting: the AI trade. This week alone, the Nasdaq-100 ETF (QQQ) has held up far better than the S&P 500 (SPY) or Dow (DIA) trackers, thanks to resilience in major technology stocks. Nvidia, Micron, and Intel are all on track to end the week in the green. Micron just posted blockbuster quarterly results — adjusted earnings of $33.42 per share against $31.61 expected, with revenue of $54.23 billion topping forecasts of $51.07 billion — and Accenture surged 16% after reporting stronger-than-expected earnings.
Meanwhile, everything else is getting hammered by soaring bond yields. The 10-year Treasury yield pushed past 5.2% this week and the 30-year traded near 5.63% — multi-decade highs. Higher yields are kryptonite for most stocks: they raise borrowing costs for companies, drag down growth-stock valuations, and give investors a fat, safe alternative to equities. As Scott Brown of Brown Technical Insights put it this week: “Tech is hanging in there, and everything else is just falling quite honestly in a straight line.”
In Canada, the same forces pushed the TSX down to a 10-week low on Thursday, with banks like RBC and TD Bank sliding as the Canadian 10-year yield held near multi-year highs. Gold climbed above $4,176 an ounce as some investors sought shelter — a classic sign that fear is running beneath the headline index levels.
What This Means for Your Portfolio
If you own a plain S&P 500 index fund, you’re fine — the giants are doing their job. But if you own individual stocks, a small-cap fund, or anything labeled “diversified,” you may be looking at losses while the headlines scream “record highs.” This is the cruel part of bad breadth: the market feels rigged when your holdings bleed and the index prints green.
Three practical takeaways:
- 1. Your benchmark might be lying to you. Comparing your portfolio to the S&P 500 right now is like comparing your salary to the average of a room that includes three billionaires. Judge your holdings against something that actually looks like them — small-cap funds against the Russell 2000, balanced funds against a balanced index.
- 2. Concentration is the risk no one priced. When five or ten stocks carry the whole market, the market is fragile. If the AI trade stumbles — a weak quarter, a guidance cut, a tariff shock — the index could drop fast with no healthy base of stocks underneath to cushion it.
- 3. Cash is finally a competitor again. With bond yields at multi-decade highs, parking money in a high-yield account or short-term bonds pays real money. That’s pulling cash away from stocks, and it’s why the selling pressure keeps building under the surface.
What Should You Do About It
Don’t panic-sell, and definitely don’t chase the AI rally at this stage — buying into a concentrated run this late is how people get hurt. Instead:
- Rebalance on a schedule, not on emotion. If tech now makes up way more of your portfolio than your plan called for, trim it back to your target allocation. Rebalancing is just buying low and selling high on autopilot.
- Check what you actually own. Many “total market” funds are now dominated by the same handful of names. If you want real diversification, the equal-weighted version of the S&P 500 exists precisely for moments like this — it holds the same 500 companies, just without the giant weighting on top.
- Keep contributing. Corrections hidden inside a rising index are exactly when dollar-cost averaging earns its keep. Your automatic contributions are buying the beaten-down average stocks at a discount while the headlines look expensive.
The Bottom Line
The market isn’t strong — it’s narrow. A handful of tech winners are masking a broad correction underneath, and history says extreme breadth like this eventually resolves one way or another. You can’t control which way, but you can control your exposure: know what you own, rebalance, and don’t mistake the index’s face for the market’s body. The average stock is struggling right now. Make sure your plan doesn’t pretend otherwise.