r/StockMarket • u/Smart_Money_HQ • 11h ago
Opinion September Seasonality
My year-end base case of 800 and optimistic scenario of 830 remain intact, although the path there is unlikely to be smooth as we move through September so trail your positions, protect profits and don’t get greedy.
Seasonality is one reason for keeping risk contained because since 1928, September has been the only month in which the S&P 500 has fallen more often than it has risen, finishing lower 55% of the time. The average return has been 1.1%, while the typical intra-month selloff has been closer to 4.7%.

ALso, the weakness has usually arrived later in the month as second half of September has averaged a −0.91% return, making it historically the weakest two-week stretch of the year. This does not guarantee another selloff, but it supports being more selective rather than chasing every move higher.

Midterm election years have made this pattern even more with September averaging a about a1.5% return and a roughly 6% drawdown. The historical path tends to weaken into month-end before improving in October and accelerating around Election Day into year-end.

That is broadly how I am approaching the next several weeks as there is a tactical window for volatility and further weakness, but this would create a potentially much better setup in October.
I also wanted to share that orporate buyback demand is likely to peak around September 8 before gradually fading through the remainder of the month and means one of the market’s largest and most consistent sources of structural buying becomes progressively weaker just as the historically more difficult second half of September approaches.

