The takeaway
Fortinet Inc shows a moderate seasonal pattern over 10 years of data — strongest in February (+7.1%) and softest in September (−0.8%).
Right now
In July, the stock has risen 50% of years, averaging +2.6% — essentially in line with the S&P 500.
The full picture
Fortinet Inc's most dependable month has been February, higher in 9 of 10 years; September has been its least reliable, up just 50% of the time.
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Month by month
The stock's clearest edge over the S&P 500 lands in February (+7.4 pts); it has trailed the market most in September (−0.6 pts).
“vs S&P” is Fortinet Inc’s average for a month minus the S&P 500’s average for that same month — isolating Fortinet Inc’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, February has closed higher 100% of the time versus 90% across the last 10 years — the pattern is holding.
Figures are the typical (median) February 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
This is a stock you can almost set a calendar by, and February is the anchor — it has closed higher in 9 of 10 Februaries, the steadiest beat on its year.
The strength looks broad-based rather than freakish: its average (+7.1%) and median (+10.0%) sit close together, so no single blow-out year is flattering the figure. Better still, that strength is the stock's own and not just a buoyant market — February has outpaced the S&P 500 by +7.4 points on average. It is the more striking for the company it keeps — February is a losing month for most of the market, where barely 49% of names gain ground.
February anchors a run, too: the December-through-June window has been the stock's reliable season. At the other end of the calendar, September has been the soft spot — the only month to average an outright loss (−0.8%), and the edge isn't year-round — the stock has trailed the S&P 500 in September. Its roughest month on record was a −22.8% August in 2023 — a reminder of how hard even a seasonal name can fall.
February has now closed higher 5 years running. Reassuringly, the tendency has held its shape: the recent five years still track the years behind them.
For a stock this dependable in February, the sharper question is the rest of the year — outside its strong stretch, the calendar gives far less to lean on.
Short answers on the stock's best month (February), its worst (September), and whether it really trades seasonally.
Yes, to a moderate degree. Since 2016 its best month (February, +7.1%) has run well ahead of its worst (September, −0.8%) — the heatmap above shows how steady that gap has been year to year.
February has been the strongest, averaging +7.1% and closing higher in 9 of 10 years since 2016.
It's the weakest, averaging −0.8% — 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