Deutsche Bank puts Sell in May back on trial. And finds it guilty of little more than luck Three summers did almost all the work The years in question are 1998, 2001 and 2002, when equity markets fell hard over the summer months. Remove those three years and the Sell in May trade would have underperformed buy-and-hold over the long run. Over the past decade, it has underperformed in eight of 10 years. In 2025, following the strategy would have cost investors 2.7 percentage points against the market. That is ...