September is a terrible time for stocks. This one is unlikely to be any different.
The stock market whipsawed investors in August as head-spinning headlines about the trade war raised hope, and just as quickly dashed it. “August has a reputation as a volatile month, and it sure delivered this year,” wrote Ryan Detrick, senior market strategist for LPL Financial, in a Friday note “Over the past month, we’ve not only seen the worst three days of the year, but many 1% swings in both directions.”
September is likely to bring more volatility, and possibly steeper losses, especially as the month has historically been a laggard.
Over the last 100 years, the Dow Jones Industrial Average has averaged a large decline during September. “Unfortunately, we’re finally at the worst month of the year from a seasonality perspective,” wrote Justin Walters of Bespoke Investment Group in a Friday note.
Over the last 50 years, the Dow has been positive just 36% of the time in September and the average decline during the month has been 0.92%. The next worst month is June, but with a much smaller average decline of 0.24%, noted Walters.
The S&P 500 shares the same pattern. If you only owned the S&P 500 in September during every year, a $100 investment starting in 1969 would now be worth just $70. “There is no other month of the year where you’d be in the red with this strategy, but the next worst month is the one preceding September (August),” wrote Walters, “As we always highlight during the summer, the August-September period is not a great time to be invested in the market.”
When digging deeper throughout the month, however, Walter found out that most of the weakness in September tends to come toward the end of the month. In fact, on a historical basis, the S&P 500 has actually been up in September throughout the first half of the month, but then gave up much of the gains in the second half, finishing the month with losses.
But the good news is, once September ends, things will start getting much brighter, entering into what has historically been the best three-month stretch of the year from October through December.
Over the last 20 years, the Dow has averaged gains of more than 1% during all three months. For the past 15 times when stocks were lower in August, the rest of the year was higher every single time. “A rough August has been typical, and history shows stocks have overcome the volatility through the rest of the year,” wrote LPL’s Detrick.
Despite the general tendency, the seasonal returns can still be impacted by many macro factors depending on the year.
According to Jim Paulsen at the Leuthold Group, an above-average market performance, rising bond yields, as well as faster growth in money supply in the months leading up to September have all proved supportive to the month’s stock performance in the Postwar era.
What’s interesting is that September is the only month that tends to benefit from rising bond yields, while all other months performed better when the six-month bond yield declines. “Perhaps this reflects investor fear, which often intensifies during the summer doldrums and into early fall,” wrote Paulsen, “If the consensus attitude is fearful, like today, falling yields may simply aggravate and accentuate those anxieties rather than boost confidence.”
Since the S&P 500 has risen by only 3.5% in the last six months—below the average since 1947—and bond yields have also been dropping, a below-average September might be on the horizon for this year, according to Paulsen. “At present, although money supply is accommodating, stock results may be challenged by the last six months’ paths of both the S&P 500 and bond yields.”
