The takeaway
Summit Therapeutics PLC shows a pronounced seasonal pattern over 10 years of data — strongest in January (+9.2%) and softest in June (−9.2%).
Right now
In July, the stock has risen 60% of years, averaging +6.1%, about +4.0 pts better than the S&P 500.
The full picture
Summit Therapeutics PLC's most dependable month has been January, higher in 7 of 10 years; June has been its least reliable, up just 30% of the time.
| Year | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
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Month by month
The stock's clearest edge over the S&P 500 lands in January (+9.4 pts); it has trailed the market most in June (−9.4 pts).
“vs S&P” is Summit Therapeutics PLC’s average for a month minus the S&P 500’s average for that same month — isolating Summit Therapeutics PLC’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, January has closed higher 60% of the time versus 70% across the last 10 years — the pattern is strengthening.
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
Strip the year back and a single month does the heavy lifting: January, up in 7 of 10 Januaries while the other eleven tend to blur together.
Its average (+9.2%) and median (+14.0%) 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 24.2% 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: January has cleared the S&P 500 by +9.4 points above the index. That consistency sets it apart from the field, where the average stock manages January only about 53% of the time.
Only July comes anywhere near it for reliability. At the other end of the calendar, June has been the soft spot — the weakest of 5 months that average a loss (−9.2%), and the edge isn't year-round — the stock has trailed the S&P 500 in June, December, and November. Its roughest month on record was a −81.8% June in 2018 — a reminder of how hard even a seasonal name can fall.
If anything it has sharpened recently — the last five Januaries run ahead of the earlier years.
The takeaway is less about when to buy than what to expect: January 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 (January), its worst (June), and whether it really trades seasonally.
Yes, to a pronounced degree. Since 2016 its best month (January, +9.2%) has run well ahead of its worst (June, −9.2%) — the heatmap above shows how steady that gap has been year to year.
January has been the strongest, averaging +9.2% and closing higher in 7 of 10 years since 2016.
It's the weakest, averaging −9.2% — 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