September has been the worst performing month for the S&P 500 since 1950, a pattern that persists over the past decade. That reputation often spooks traders into cutting exposure reflexively—without checking whether market conditions actually warrant it.
This September is different.
Ryan Detrick, chief market strategist at Carson Group, cuts to the real driver: "Usually the bad Septembers historically are when you have a weak market coming into it. That's not the case right now."
The numbers back him up. SPY has climbed 5.47 percent over the past month and is up 12.82 percent year to date. The VIX sits at 14.51—well within the low-volatility zone and far from the stress levels that preceded historical September selloffs.
Market breadth is the strongest tell. Almost 70 percent of S&P 500 stocks are trading above their 200-day moving averages, signaling broad participation in the advance rather than gains concentrated in a handful of mega-cap names. That breadth pattern historically precedes strong months, not weak ones.
Earnings cement the case. Matt Powers, managing partner at Carson Group, notes that current earnings growth is the strongest since Q3 2021. Ten of 11 S&P 500 sectors reported earnings growth, with nearly all posting double-digit increases. That's a sharp contrast to prior cycles where September declines coincided with falling earnings revisions.
Consumer sentiment offers a brake on the narrative—the University of Michigan sentiment index rose to 55.2 in July 2026 from June but remains below neutral levels. Demand exists but isn't euphoric.
For equity allocators, the message is clear: this September enters with structural tailwinds that historically break the losing streak. Position accordingly.
