GSK (GSK.L) Seasonality
Recurring seasonal patterns for GSK.L — the calendar windows where GSK has historically tended to rise or fall, with the win rate (how often it repeated) and average return for each, based on the last 10 years of price history.
GSK.L seasonality at a glance
Over the last 10 years, GSK.L's strongest seasonal window has been Dec 18 – Jan 17: it ended higher in 10 of 10 years (100% win rate) with an average return of +3.52% across a 30-day hold. On the weak side, GSK.L has historically declined between Nov 9 – Nov 19, falling in 9 of 10 years (average -2.21%).
In total, our analysis finds 362 recurring seasonal windows for GSK — 244 bullish and 118 bearish. The next high-win-rate window, Aug 22 – Sep 21, opens in 26 days. These figures describe historical behaviour only — not a forecast.
GSK.L's upcoming & recent seasonal patterns
Holding period:10-day20-day30-dayOrdered by season — windows opening soon first, plus a couple of recently completed high-performers. Holding-period colors help you compare durations at a glance.
| Status | Seasonal window | Hold | Avg return | Win rate | This year |
|---|---|---|---|---|---|
| Completedended 117d ago | Mar 12 – Apr 1 | 20d | +2.66% | 80% | +3.74% |
| Completedended 119d ago | Mar 20 – Mar 30 | 10d | +2.25% | 80% | +5.77% |
| Upcomingin 26d | Aug 22 – Sep 21 | 30d | -1.66% | 80% | — |
| Upcomingin 27d | Aug 23 – Sep 22 | 30d | -1.40% | 80% | — |
| Upcomingin 28d | Aug 24 – Sep 23 | 30d | -1.33% | 80% | — |
| Upcomingin 42d | Sep 7 – Sep 17 | 10d | -1.09% | 80% | — |
| Upcomingin 101d | Nov 5 – Dec 5 | 30d | -2.00% | 80% | — |
Win rate = how often the pattern repeated in the same direction. Average return = the mean move across all analysed years. Past performance does not guarantee future results.
Explore GSK.L seasonality in full
See the seasonal curve chart, filter by win rate and return, and track upcoming windows — free during beta.
GSK.L seasonality FAQ
What has historically been the best month to buy GSK.L stock?
Based on the last 10 years of price data, GSK.L's strongest seasonal window starts in December: Dec 18 to Jan 17, which ended higher in 10 of 10 years (100% win rate) with an average return of +3.52%. Past seasonal patterns do not guarantee future performance.
What is GSK.L's strongest seasonal pattern?
GSK.L's highest-win-rate pattern in our data is the Dec 18 – Jan 17 window (30-day hold): up in 10 of the last 10 years with an average move of +3.52%.
When has GSK.L historically performed worst?
GSK.L's weakest recurring window has been Nov 9 to Nov 19, declining in 9 of 10 years with an average return of -2.21%.
How reliable are GSK.L's seasonal patterns?
Each GSK.L pattern is scored by its historical win rate — the share of the last 10 years it repeated in the same direction. GSK.L currently shows 362 recurring windows (244 bullish, 118 bearish). Seasonality describes historical tendencies only; it is not a prediction, and past performance does not guarantee future results.
What is GSK.L stock seasonality?
Stock seasonality is the tendency of a stock to perform in a similar way during the same period each year. By analysing GSK's price history across many years, SeasonalityX identifies recurring calendar windows — exact start and end dates — where GSK.L has repeatedly risen (bullish) or fallen (bearish). Each pattern is scored by its win rate and average return so you can judge how reliable and how strong it has been.
Seasonality is one input among many — it works best alongside your own research and risk management. Learn more in our guide to seasonal analysis and the tutorials.