Stock Market Seasonality: SPY & QQQ Average Returns by Month
How the S&P 500 (SPY) and Nasdaq-100 (QQQ) have traded by calendar month and across the average trading year — full history, the past 20 years and the past 10 years, with win rates. A base-rate tendency measured over decades, not a forecast.
The reading · SPY
Since 1993, the strongest calendar month for the S&P 500 (SPY) has been November (+2.44% average) and the weakest September (-0.90%). June — the current month — has averaged -0.03% with a 53% positive rate across 34 years. Seasonality is a base-rate tendency measured over decades, not a forecast for any single year.
Strongest stretch of the year has historically been November through April; the “worst six months” (May–October) sit behind the “sell in May” adage. SPY daily (1993–present).
Average return by month — S&P 500 (SPY)
The average return for each calendar month, compared across three lookbacks. The shaded column is the current month (June). Watch whether a month is strong across all three windows (structural) or only recently (a newer regime).
The average trading year — S&P 500 (SPY)
Each year's cumulative return, normalized to the prior year-end and averaged across the window — the shape of a typical year. The green band marks the current month.
Monthly statistics — S&P 500 (SPY)
| Month | Full avg | Full win% | 20Y avg | 10Y avg | Years |
|---|---|---|---|---|---|
| January | +0.76% | 61% | +0.27% | +2.11% | 33 |
| February | -0.02% | 52% | +0.15% | -0.40% | 33 |
| March | +0.54% | 59% | +0.53% | -1.22% | 34 |
| April | +1.96% | 74% | +2.45% | +2.20% | 34 |
| May | +1.21% | 74% | +1.18% | +2.02% | 34 |
| June(current) | -0.03% | 53% | -0.33% | +1.20% | 34 |
| July | +1.48% | 64% | +2.67% | +3.51% | 33 |
| August | -0.04% | 64% | +0.23% | +1.16% | 33 |
| September | -0.90% | 52% | -0.99% | -1.73% | 33 |
| October | +1.68% | 64% | +1.01% | +1.07% | 33 |
| November | +2.44% | 76% | +2.35% | +4.38% | 33 |
| December | +0.46% | 64% | +0.17% | -0.41% | 33 |
Strongest: November (+2.44%). Weakest: September (-0.90%).
How Stock Market Seasonality Works
- 1Compute a return for every calendar monthFrom each symbol's daily history we take month-end closing prices and measure the return from one month-end to the next. SPY history goes back to 1993 and QQQ to 1999, giving 30+ and 25+ observations for each calendar month.
- 2Average each month over three lookbacksFor every calendar month we report the average return and win rate (% of years positive) over the full history, the trailing 20 years and the trailing 10 years. Comparing the three reveals whether a seasonal tendency is structural or has only shown up recently.
- 3Build the average seasonal pathFor each year we normalize the close to the prior year-end and track the cumulative return through the year, then average those paths across every year in the selected window (10, 15, 20 years or all history). The result is the shape of a typical trading year — the slow summer, the autumn dip, the year-end rally.
- 4Mark the current monthBoth charts highlight the calendar month you are in now, so you can read this month's historical tendency at a glance — its average return, its win rate, and where it sits on the average year's path.