The S&P 500 has a peculiar pattern that catches traders off guard every few years—what some call the midterm curse. This seasonal phenomenon tends to show weakness during specific calendar periods, creating predictable dips that savvy investors have learned to anticipate.

While this traditionally applies to equity markets, crypto traders shouldn't ignore it. When traditional finance experiences headwinds, capital often rotates across asset classes, affecting risk appetite and liquidity flows into digital assets. Understanding these seasonal traps means recognizing when broader market sentiment could shift unexpectedly.

The pattern isn't guaranteed, but the data shows repeating cycles. Years divisible by certain intervals historically see pullbacks, suggesting market memory and behavioral finance at play. Whether it's year-end profit-taking, institutional rebalancing, or simply momentum exhaustion, the effect persists.

For those trading altcoins or tracking Bitcoin correlation with traditional markets, watching equity indexes for these seasonal signals can provide an edge. When the S&P 500 enters its vulnerable window, prepare for volatility spillovers into crypto.