Sell in May and Go Away? Maybe Not

The sharp rebound from the March lows has pushed most major equity indexes back to record highs. This upside momentum has been fueled in part by signs of de-escalation with Iran and growing expectations that the Strait of Hormuz could reopen soon. While the geopolitical environment remains fluid on a day-to-day basis, markets appear to be assigning a higher probability to a relatively near-term U.S. exit from the Middle East, alongside a normalization in global supply chains that could ultimately pressure oil prices lower.

Heading into month-end, the S&P 500 is up 9.2% as of April 29, putting it on pace for its strongest April performance since 2020. Support for equities has also come from solid first-quarter earnings and economic data that have shown limited signs of deterioration.

However, not all markets are sending the same signal. The physical oil market continues to reflect the risk of a “higher-for-longer” regime, suggesting tighter underlying supply conditions (a theme we explored further in Paper vs. Physical: What Tighter Oil Supplies Could Mean). The fixed income market also paints a similar story of lingering inflation risk as Treasury yields remain uncomfortably high. Although it's important to note, yields have been less responsive to higher oil prices this month versus last month.

May Seasonality: Weak History, Strong Recent Trends

As the calendar turns to May, seasonal trends re-enter the conversation. Historically, May has been a relatively lackluster month for equities. Since 1950, the S&P 500 has delivered an average return of just 0.4% and finished higher 62% of the time, ranking as the fifth-weakest month of the year when it comes to returns.

Read more: Paper vs. Physical: What Tighter Oil Supplies Could Mean

More recently, however, the data tells a different story. Since 2013, May has averaged a stronger 1.5% return, with 12 of the past 13 years ending in positive territory. This suggests that while long-term trends remain subdued, recent performance has been far more constructive.