There is a difference between an index that is earning its keep and an index that has a few names doing the work while everyone congratulates the whole roster. The headline number does not tell you which one you own. You have to take it apart, writes Michael Gayed, editor of The Lead-Lag Report.
Take the S&P 500 Index (^SPX) apart right now and something uncomfortable falls out. For the second quarter of 2026, the blended year-over-year earnings growth rate for the index is 24.7%, the second consecutive quarter above 20%. That is a genuinely strong print. It is also, in large part, an illusion of breadth.
Remove two companies, Micron Technology Inc. (MU) and Nvidia Corp. (NVDA), and the same figure falls to 16.8%. Two stocks out of five hundred are supplying nearly eight of the twenty-five growth points the index is reporting.
The consensus reads 24.7% and concludes earnings growth is robust. I read the same release and see an index whose reported profit growth is increasingly a function of a handful of semiconductor and energy names. It’s riding a forward multiple that leaves no cushion, at exactly the point in the cycle when quality usually erodes before the level does.
None of this is a call to abandon equities, and it is emphatically not a view on any individual company. Micron, Nvidia, and the rest of the concentration cohort are extraordinary businesses. The observation is about the index-level earnings narrative, not about the merits of the names carrying it.
But the regime signal is late-cycle. The prudent posture in a late-cycle regime is to reduce reliance on the most concentrated part of the return, not to lean into it because the composite reads clean.
