It's all Trump's fault for not taking the weekend off! Deutsche Bank: U.S. stocks now have "Black Monday" and "Deadly Friday"

The U.S. stock market in 2025 is exhibiting quite an unusual trend. Although it is generally on the rise, Mondays and Fridays have become "disaster zones."

Deutsche Bank analyst Jim Reid released a new research report on the 25th, revealing this abnormal phenomenon. The report compared the daily performance of the S&P 500 index in 2025 with the long-term average from 1928 to 2024. The results were astonishing: In 2025, Fridays performed terribly, and Mondays were only slightly better.

This is in stark contrast to historical norms. Over the long term, Fridays are usually one of the best-performing days of the week for U.S. stocks, while Mondays are typically the worst.

Deutsche Bank analysts link this to the "headline risk" during the Trump era. They believe the possible reason behind this is that the market is concerned about potential negative news over the weekend, leading investors to reduce their risk exposure before the weekend. The poor performance on Mondays indicates that these threats have not been completely eliminated.

"Deadly Friday": More Terrifying than Black Monday?

Deutsche Bank's research shows that from a historical perspective, the best-performing trading day for the U.S. stock market from 1928 to 2024 was Wednesday, followed by Friday, while Monday was the worst-performing day.

This aligns with common patterns in investor psychology: "As the weekend approaches, we tend to become more optimistic and cheerful!"

However, the market in 2025 has completely broken this traditional pattern. By comparing nearly a century of historical data with this year's market performance, the research indicates that the daily patterns of the U.S. stock market have changed significantly. Fridays have become the worst-performing trading day, closely followed by Mondays, while mid-week periods (especially Tuesdays and Wednesdays) are performing relatively well.

Deutsche Bank's chart shows the average price changes of the S&P 500 index on each trading day of the week in 2025 compared to 1928 to 2024. On Fridays in 2025, the average price trend is 0.4 percentage points below the average level, while historically, Friday's price trend was nearly 0.1 percentage points above the average level.

On Mondays, the price trend is about 0.2 percentage points below the average level, while historically, Monday's price trend was about 0.1 percentage points below the average level.

The global market in February is quite turbulent. First, DeepSeek emerged, shaking Silicon Valley, followed by Trump's announcement of imposing tariffs on Canada and Mexico, and then the proposal of "reciprocal tariffs," catching the market off guard. Previously, Goldman Sachs' top trader Brian Garrett couldn't help but exclaim that weekends have now become trading periods, and the volatility of the S&P 500 has already reacted to this.

For many market traders, the recent increase in volatility on Mondays and Fridays is no longer a secret

Weekend "Light Armored": The New Normal for Traders?

Deutsche Bank analysts believe that the unusual trend in the U.S. stock market in 2025 may be related to the "headline risk" during the Trump era.

The report points out that the market may be concerned about potential negative news over the weekend, such as tariffs imposed on Mexico and Canada. This concern leads investors to tend to reduce risk exposure on Fridays.

"The market seems to have formed a pattern: negative news may emerge at the end of each week, and investors tend to reduce risk exposure to prevent the situation from escalating over the weekend."

This has left U.S. media, which must keep up with current events, exhausted. Some media have previously publicly called out, "President Trump, can you take a day off..."

What’s more noteworthy is that Monday's performance did not show significant improvement, indicating that market risks have not fully dissipated after the weekend.

Although Monday and Friday performed poorly, the Deutsche Bank report also notes that by midweek, the market usually digests these negative news and gradually returns to calm. The report states that the performance of the U.S. stock market typically improves on Tuesday, Wednesday, and Thursday.

In the face of this unusual trading pattern, Deutsche Bank analyst Jim Reid raises a key question: Is this phenomenon temporary or could it become the new normal? The report suggests that as long as geopolitical tensions and policy uncertainties persist, this trading pattern may continue.

"In a world filled with headline risks, traders may continue to prefer to lighten their positions before the weekend, being more cautious than in calmer markets."