The takeaway
Penumbra Inc shows a pronounced seasonal pattern over 10 years of data — strongest in January (+8.0%) and softest in May (−1.2%).
Right now
In July, the stock has risen 60% of years, averaging +2.7%, about +0.6 pts better than the S&P 500.
The full picture
Penumbra Inc's most dependable month has been January, higher in 8 of 10 years; May has been its least reliable, up just 40% of the time.
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Month by month
The stock's clearest edge over the S&P 500 lands in January (+8.2 pts); it has trailed the market most in May (−2.0 pts).
“vs S&P” is Penumbra Inc’s average for a month minus the S&P 500’s average for that same month — isolating Penumbra Inc’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, January has closed higher 80% of the time versus 80% across the last 10 years — the pattern is holding.
Figures are the typical (median) January 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
Dependability is the through-line here. January stands out, higher in 8 of 10 Januaries, but it heads a clutch of months that pull the year reliably upward.
Its average (+8.0%) and median (+10.7%) 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 January ranges by 19.0% 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: January has cleared the S&P 500 by +8.2 points above the index. That consistency sets it apart from the field, where the average stock manages January only about 53% of the time.
A few other months pull their weight: February, April, and June have also closed higher more often than not. The weaker half of the year is plainer: May has been the soft spot — the weakest of 3 months that average a loss (−1.2%), and the edge isn't year-round — the stock has trailed the S&P 500 in May, December, and March. Its roughest month on record was a −24.1% April in 2022 — a reminder of how hard even a seasonal name can fall.
Reassuringly, the tendency has held its shape: the recent five years still track the years behind them.
The takeaway is less about when to buy than what to expect: January aside, the stock's months offer little reliable tilt.
Short answers on the stock's best month (January), its worst (May), and whether it really trades seasonally.
Yes, to a pronounced degree. Since 2016 its best month (January, +8.0%) has run well ahead of its worst (May, −1.2%) — the heatmap above shows how steady that gap has been year to year.
January has been the strongest, averaging +8.0% and closing higher in 8 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