The takeaway
Appian Corp shows a pronounced seasonal pattern over 9 years of data — strongest in August (+11.0%) and softest in December (+0.8%).
Right now
In July, the stock has risen 56% of years, averaging +1.7% — essentially in line with the S&P 500.
The full picture
Appian Corp's most dependable month has been August, higher in 6 of 9 years; December has been its least reliable, up just 22% of the time.
| Year | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Win rate % | ||||||||||||
| Median return % | ||||||||||||
| 2025 | ||||||||||||
| 2024 | ||||||||||||
| 2023 | ||||||||||||
| 2022 | ||||||||||||
| 2021 | ||||||||||||
| 2020 | ||||||||||||
| 2019 | ||||||||||||
| 2018 | ||||||||||||
| 2017 | — | — | — | — |
Month by month
The stock's clearest edge over the S&P 500 lands in January (+14.0 pts); it has trailed the market most in March (−7.0 pts).
“vs S&P” is Appian Corp’s average for a month minus the S&P 500’s average for that same month — isolating Appian Corp’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, August has closed higher 40% of the time versus 67% across the last 9 years — the pattern is weakening.
Figures are the typical (median) August return and how often it rose — the last 5 years versus the last 9(the heatmap’s default window). This verdict stays anchored to that 9-year window even if you zoom the chart, so it never disagrees with the badges above.
In plain English
The year leans August's way without overwhelming the rest of it: the stock has closed higher in 6 of 9 Augusts, its most dependable month if not a dominant one.
Its average (+11.0%) and median (+10.2%) land within a hair of each other — the tell of steady, year-after-year gains rather than one outlier doing the work. That reliability comes with real swings, mind — even August ranges by 17.3% from year to year, so any single year can land far from the average. Crucially, the gain is the stock's own rather than a rising tide's: August has cleared the S&P 500 by +10.7 points above the index. That consistency sets it apart from the field, where the average stock manages August only about 52% of the time.
A few other months pull their weight: January, May, and June have also closed higher more often than not. At the other end of the calendar, December is the year's low point, though even there the stock has stayed positive on average (+0.8%), a sign every month leans up, and the edge isn't year-round — the stock has trailed the S&P 500 in March, February, and October. Its roughest month on record was a −28.9% March in 2021 — a reminder of how hard even a seasonal name can fall.
The pattern has softened of late, August's last five years slipping below its longer-run record.
Treat it as a tendency rather than a rule — seasonality describes the past, not a promise. With a short 9-year record and returns that swing hard year to year, the signal is best held loosely.
Short answers on the stock's best month (August), its worst (December), and whether it really trades seasonally.
Yes, to a pronounced degree. Since 2017 its best month (August, +11.0%) has run well ahead of its worst (December, +0.8%) — the heatmap above shows how steady that gap has been year to year.
August has been the strongest, averaging +11.0% and closing higher in 6 of 9 years since 2017.
It's the weakest month, but it has still averaged a small gain (+0.8%) — quiet rather than genuinely bad.
Explore
These names have the strongest July track records on record — a starting point for comparison.
Before you trade