Nasdaq-100 (NDX / QQQ)
Most bullish months (highest % of up months & positive average returns):
- April, July, October, November — these months show the most consistent “win rates” and often the largest average gains over 20-year windows on QQQ/NDX seasonality tools. September is the notable exception on the weak side.
Most bearish month:
- September — commonly the lowest win rate and often a negative average month for QQQ/NDX seasonality. February and June sometimes screen as softer as well (but less consistently than September).
S&P 100 (OEX or SPY)
Most bullish months:
- April, July, November, December — OEX’s 20-year seasonality (via $OEX pages) typically shows these as the most reliable “up” months, with above-median win rates and positive averages.
Most bearish month:
- September — repeatedly the weakest by win rate, with June/August occasionally joining the laggards depending on the exact 20-year window and data provider.
Practical Takeaways
- For the Nasdaq-100, April, July, October, November historically stack the odds (highest win rates, solid average gains). September is the month to be most cautious about.
- For the S&P 100, April, July, November, December generally screen strongest on 20-year stats; September is usually the laggard.
- Seasonality is context, not a signal by itself. Macro catalysts, earnings season clustering (Jan/Apr/Jul/Oct), rebalancing, and tax/flows can overwhelm averages in any one year. Consider blending seasonality with trend, breadth, and risk controls.
Lowest Volume Periods of the Year
Late December (Christmas – New Year’s “Holiday Week”)
- The lowest volume week of the year is almost always the last week of December, between Christmas and New Year’s Day.
- Many institutional traders, hedge funds, and portfolio managers are away, and retail activity alone can’t keep volume high.
- For SPY and QQQ, volume often drops 30–50% below the yearly average in this period.
Mid-to-Late August (Summer “Doldrums”)
- The second-lowest volume period is the last two weeks of August.
- U.S. and European traders are typically on summer vacation, and there are fewer catalysts (earnings season winds down, Fed usually quiet).
- QQQ often sees sharper slowdowns than SPY here, since tech trader’s step back after July earnings.
- Average daily volume can be 20–40% lower than normal.
Written by Michael DiGioia, Director of Education
Mike is available for One-on-One Coaching. Learn More
