"Will the September Curse Strike Again?"...Bitcoin (BTC) Falls 8 Out of 13 Times

▲ Bitcoin (BTC), S&P 500/AI Generated Image

As Bitcoin (Bitcoin, BTC) enters September, statistically the weakest month of the year, immediately after a roughly 25% surge in August, concerns about increased volatility are growing.

According to Decrypt on September 1 (local time), Bitcoin has fallen 8 out of 13 Septembers completed since 2013. Data from CoinGlass shows that the average return for September was -2.97%, and the median was -2.44%. Both figures are the lowest for the year. During the same period, the average return for June was -1.59%, while other months recorded positive returns on average.

The stock market was also not free from September's weakness. The S&P 500 has fallen an average of about 0.6% in September since 1945, and extending the range back to 1928, the average decline increases to about 1.1-1.2%. The year 2026 also carried the burden of being a US midterm election year. In the last 10 midterm election cycles since 1986, the US stock market fell an average of about 17% from its previous high before forming a bottom around September 2nd.

Last year, the September curse was unusually broken. Bitcoin dropped to as low as $111,986 intraday in September 2025 but rebounded thanks to ETF fund inflows, closing the month with a 5.16% gain. However, after hitting an all-time high above $126,000 on October 6th, the situation changed dramatically. Following US President Donald Trump's threat of 100% tariffs on Chinese imports on October 10th, $19 billion worth of margin positions were liquidated within 24 hours, and 1.6 million investors experienced liquidations. The monthly return for October was -3.69%.

This year, monetary policy is considered the biggest variable. Bitcoin rose by about 25% in August, marking its strongest August since 2021, and then started September at around $77,500. Fed Chairman Kevin Warsh pointed out that the Personal Consumption Expenditures (PCE) price index recorded an annual rate of 3.7%. CME FedWatch reflected a 68.2% probability of a rate hike in September. The 30-year US Treasury yield also rose to 5.28% at the end of August, approaching levels seen before the 2008 financial crisis.

The market's next turning point is the Federal Reserve (Fed) meeting on September 15-16. If the Fed raises interest rates, it would be the first increase since 2023. In the preceding tightening cycle of 2022-2023, Bitcoin fell by about 65%, dropping to $15,500 in November 2022. This September, a scenario has formed where both historical seasonal weakness and the risk of interest rate hikes simultaneously pressure the market.

[Article Key Summary]

-Bitcoin has fallen 8 out of 13 Septembers since 2013, with an average return of -2.97%, making it the weakest month of the year.

-In 2025, Bitcoin avoided seasonal weakness with a 5.16% gain in September, but $19 billion worth of margin positions were liquidated the following month.

-In 2026, with a 68.2% probability of a September interest rate hike reflected, both seasonal weakness and monetary policy burdens are highlighted simultaneously.

*Disclaimer: This article is for investment reference only, and we are not responsible for any investment losses based on it. The content should be interpreted for informational purposes only.*