Why the ‘Halloween Indicator’ isn’t working — and what smart investors are doing instead

The "Halloween indicator" — the seasonal adage urging investors to sell equities in May and return in November — has failed its followers this year. Rather than declining through the summer months, stocks rallied, leaving those who stepped aside on the sidelines of gains they would otherwise have captured.

The episode illustrates a broader point about market lore: seasonal patterns are observations of past behaviour, not dependable forecasts. They rest on averages that can be overwhelmed by any number of variables — earnings, interest rates, or shifts in sentiment — and by the time a pattern becomes widely known, its advantage may already be diminished.

What matters more for investors is the lesson the indicator's stumble reinforces: time in the market has generally proven more reliable than timing it. Rather than repositioning around calendar dates, many investors focus on diversification, consistent contributions, and an asset allocation matched to their goals and tolerance for risk. Seasonal signals can be interesting to study, but they are a weak foundation for portfolio decisions.