The takeaway
PTC Therapeutics Inc shows a pronounced seasonal pattern over 10 years of data — strongest in November (+14.5%) and softest in December (−0.2%).
Right now
In July, the stock has risen 60% of years, averaging +0.7%, roughly 1.5 pts behind the S&P 500.
The full picture
PTC Therapeutics Inc's most dependable month has been November, higher in 7 of 10 years; December 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 November (+12.1 pts); it has trailed the market most in October (−7.3 pts).
“vs S&P” is PTC Therapeutics Inc’s average for a month minus the S&P 500’s average for that same month — isolating PTC Therapeutics Inc’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, November has closed higher 80% of the time versus 70% across the last 10 years — the pattern is strengthening.
Figures are the typical (median) November 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. November stands out, higher in 7 of 10 Novembers, but it heads a clutch of months that pull the year reliably upward.
Its average (+14.5%) and median (+11.8%) 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 November ranges by 24.1% 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: November has cleared the S&P 500 by +12.1 points above the index. Some of that is a strong month market-wide, mind — November rises for about 62% of stocks — so the tendency is real if not unique.
A few other months pull their weight: February, April, and May have also closed higher more often than not. At the other end of the calendar, December is the year's quietest corner, essentially flat on average, and the edge isn't year-round — the stock has trailed the S&P 500 in October, February, and March. Its roughest month on record was a −67.7% February in 2016 — a reminder of how hard even a seasonal name can fall.
If anything it has sharpened recently — the last five Novembers run ahead of the earlier years.
The takeaway is less about when to buy than what to expect: November aside, the stock's months offer little reliable tilt. With returns that swing hard year to year, the signal is best held loosely.
Short answers on the stock's best month (November), its worst (December), and whether it really trades seasonally.
Yes, to a pronounced degree. Since 2016 its best month (November, +14.5%) has run well ahead of its worst (December, −0.2%) — the heatmap above shows how steady that gap has been year to year.
November has been the strongest, averaging +14.5% and closing higher in 7 of 10 years since 2016.
It's the weakest, averaging −0.2% — 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.
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