The Potential Risks Following a Strong August Market
Ryan Detrick, the Chief Market Strategist at Carson Group LLC, has issued a cautionary statement regarding the solid performance of the stock market in August 2025. The S&P 500's notable gains could signal potential difficulties for investors in the upcoming month. Detrick raised an important question on social media: "Could a highly successful August spell trouble for September?" He referenced a historical trend that details how a robust August—defined as a month with more than a 1% increase and at least five all-time highs—has consistently led to challenges in September.
Understanding Historical Patterns
According to comprehensive data from Carson Investment Research, a pattern has emerged over several decades. From 1950 through 2025, any time the S&P 500 exhibited gains of over 1% and achieved five or more all-time highs in August, September's performance followed a consistent trend of decline. The statistics revealed an alarming fact—the returns in September have been negative 100% of the time following such an August.
August 2025 Statistics: A Cause for Concern
In the case of August 2025, the S&P 500 rose by 1.9%, hitting a high of 6,508 points prior to the end of the month and setting five new records. This reflects the historical cautionary signs that have preceded every notable decline in September. The SPDR S&P 500 ETF Trust (SPY) closed at $644.95, reflecting a slight decrease of 0.61% at that time.
Market Data Indicates a Possible Downturn
The historical data provides several concerning statistics regarding the stock market's performance in September when preceded by a strong August:
- Average September return: -2.3%
- Median September return: -1.9%
- Success rate: 0.0%
This trend has persisted through eight previous occurrences from 1961 to 2021. Some notable declines include the drastic drop of -8.9% in September 2008 and a less severe fall of -4.8% in September 2021.
Wall Street's Consensus on September
September has a reputation as Wall Street's most challenging month. Data from various financial institutions, including insights from Bank of America, highlight the S&P 500's historical performance, showing it has faced declines in 56% of September months since 1928, typically averaging a 1.17% loss during that timeframe.
Paul Ciana, a technical strategist at Bank of America, remarked on the reliability of negative trends in September, underscoring the need for investors to approach this month with caution due to historical patterns.
The Current Market Climate and Future Outlook
This warning comes amidst speculations regarding potential Federal Reserve rate cuts. Recent data from the CME FedWatch Tool indicates there is an 89.7% probability of a 25-basis-point reduction in interest rates occurring this month, which could affect market behavior. Observing past patterns, there have been various August surges that ultimately resulted in September declines, including noteworthy years such as 1987 (+3.5% followed by -2.4%), 2020 (+7.0% followed by -3.9%), and 2014 (+3.8% followed by -1.6%).
Frequently Asked Questions
What does a strong August mean for September?
A strong performance in August, particularly if it exceeds 1% and includes multiple all-time highs, has historically indicated a likelihood of negative returns in September.
What are the statistics for September returns?
Historical data shows that the average return for the S&P 500 in September is -2.3%, with a median return of -1.9% when preceded by a strong August.
How often has September resulted in losses?
According to historical trends, September has seen negative returns 100% of the time following a strong August with at least five all-time highs.
Why is September known as a challenging month for investors?
September is known for historically being Wall Street's worst month, with losses recorded in 56% of past September months since 1928.
What should investors consider moving into September?
Investors should be cautious due to historical trends suggesting September declines following strong August performances, particularly when looking at the broader market context.
