The takeaway
Insulet Corporation shows a pronounced seasonal pattern over 10 years of data — strongest in August (+9.8%) and softest in December (−1.2%).
Right now
In July, the stock has risen 50% of years, averaging +2.0% — essentially in line with the S&P 500.
The full picture
Insulet Corporation's most dependable month has been August, higher in 9 of 10 years; December has been its least reliable, up just 20% 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 | ||||||||||||
| 2016 |
Month by month
The stock's clearest edge over the S&P 500 lands in August (+9.5 pts); it has trailed the market most in October (−4.6 pts).
“vs S&P” is Insulet Corporation’s average for a month minus the S&P 500’s average for that same month — isolating Insulet Corporation’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, August has closed higher 80% of the time versus 90% across the last 10 years — the pattern is weakening.
Figures are the typical (median) August return and how often it rose — the last 5 years versus the last 10(the heatmap’s default window). This verdict stays anchored to that 10-year window even if you zoom the chart, so it never disagrees with the badges above.
In plain English
Strip the year back and a single month does the heavy lifting: August, up in 9 of 10 Augusts while the other eleven tend to blur together.
Its average (+9.8%) and median (+12.3%) 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 15.2% 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 +9.5 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, March, and June have also closed higher more often than not. The weaker half of the year is plainer: December has been the soft spot — the weakest of 4 months that average a loss (−1.2%), and the edge isn't year-round — the stock has trailed the S&P 500 in October, September, and December.
At its steadiest, August strung together 7 straight positive years. The pattern has softened of late, August's last five years slipping below its longer-run record.
The takeaway is less about when to buy than what to expect: August aside, the stock's months offer little reliable tilt.
Short answers on the stock's best month (August), its worst (December), and whether it really trades seasonally.
Yes, to a pronounced degree. Since 2016 its best month (August, +9.8%) has run well ahead of its worst (December, −1.2%) — the heatmap above shows how steady that gap has been year to year.
August has been the strongest, averaging +9.8% and closing higher in 9 of 10 years since 2016.
It's the weakest, averaging −1.2% — historically a soft spot, though it still varies from year to year.
Explore
These names have the strongest July track records on record — a starting point for comparison.
Before you trade