The old market mantra of “sell in May and go away” looks increasingly irrelevant in the Trump era.
Analysis from IG shows the S&P 500 has delivered average gains of 9.5% between May and October during Donald Trump’s presidency.
That compares with just 1.3% in non-Trump years over the past two decades.
Across the Atlantic, the FTSE 100 has stuck more closely to tradition. The index continues to show a summer lull, with the pattern even more pronounced during the Trump years.
The divergence comes down to composition, IG says, with the US benchmark is dominated by domestic-focused technology groups, which benefit from deregulation and strong internal demand.
The constituents of the London index, by contrast, generate more than 80% of its revenues overseas.
Angeline Ong, senior analyst at IG, said this means "the FTSE tends to get caught in the crossfire while the S&P 500 keeps surfing that domestic wave".
In the past day, markets have “swapped fear for complacency," said Ong, "that’s the sweet spot where Trump thrives, because complacent markets give him free rein to do whatever he wants".
Ong suggested any complacency was only on the surface, with current options market bets suggesting oil is being bid aggressively, with positioning pointing to prices as high as $200 a barrel in August.
Metals are also attracting attention, with supply constraints emerging after heavy demand linked to the conflict that began in February.
So while the market appears less seasonal, it is no less sensitive to where risk sits.