The takeaway
F5 Networks Inc shows a moderate seasonal pattern over 10 years of data — strongest in May (+2.0%) and softest in April (−1.5%).
Right now
In July, the stock has risen 60% of years, averaging +5.1%, about +3.0 pts better than the S&P 500.
The full picture
F5 Networks Inc's most dependable month has been May, higher in 8 of 10 years; April has been its least reliable, up just 20% of the time.
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Month by month
The stock's clearest edge over the S&P 500 lands in November (+4.0 pts); it has trailed the market most in April (−3.1 pts).
“vs S&P” is F5 Networks Inc’s average for a month minus the S&P 500’s average for that same month — isolating F5 Networks Inc’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, May has closed higher 80% of the time versus 80% across the last 10 years — the pattern is holding.
Figures are the typical (median) May 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. May stands out, higher in 8 of 10 Mays, but it heads a clutch of months that pull the year reliably upward.
Its average (+2.0%) and median (+3.3%) land within a hair of each other — the tell of steady, year-after-year gains rather than one outlier doing the work. Crucially, the gain is the stock's own rather than a rising tide's: May has cleared the S&P 500 by +1.3 points above the index. That consistency sets it apart from the field, where the average stock manages May only about 55% of the time.
The strength clusters rather than stands alone — May–July forms a firm stretch that carries much of the year. On the other side of the ledger, April has been the soft spot — the weakest of 3 months that average a loss (−1.5%), and the edge isn't year-round — the stock has trailed the S&P 500 in April, October, and March. Its roughest month on record was a −22.7% October in 2025 — 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: May aside, the stock's months offer little reliable tilt.
Short answers on the stock's best month (May), its worst (April), and whether it really trades seasonally.
Yes, to a moderate degree. Since 2016 its best month (May, +2.0%) has run well ahead of its worst (April, −1.5%) — the heatmap above shows how steady that gap has been year to year.
May has been the strongest, averaging +2.0% and closing higher in 8 of 10 years since 2016.
It's the weakest, averaging −1.5% — 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