The takeaway
ACI Worldwide Inc shows a moderate seasonal pattern over 10 years of data — strongest in December (+4.7%) and softest in October (−0.5%).
Right now
In July, the stock has risen 50% of years, averaging +0.9%, roughly 1.3 pts behind the S&P 500.
The full picture
ACI Worldwide Inc's most dependable month has been December, higher in 7 of 10 years; October 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 December (+3.7 pts); it has trailed the market most in May (−2.5 pts).
“vs S&P” is ACI Worldwide Inc’s average for a month minus the S&P 500’s average for that same month — isolating ACI Worldwide Inc’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, December has closed higher 80% of the time versus 70% across the last 10 years — the pattern is strengthening.
Figures are the typical (median) December 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 December is the anchor — it has closed higher in 7 of 10 Decembers, the steadiest beat on its year.
The strength looks broad-based rather than freakish: its average (+4.7%) and median (+3.4%) sit close together, so no single blow-out year is flattering the figure. That reliability comes with real swings, mind — even December ranges by 9.1% from year to year, so any single year can land far from the average. Better still, that strength is the stock's own and not just a buoyant market — December has outpaced the S&P 500 by +3.7 points on average. Few peers keep such company in December — the typical stock clears it just 58% of the time.
It doesn't stand entirely alone — January and May have leaned firm as well, if less emphatically. On the other side of the ledger, October 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 May, October, and September. Its roughest month on record was a −19.8% February in 2020 — a reminder of how hard even a seasonal name can fall.
If anything it has sharpened recently — the last five Decembers run ahead of the earlier years.
For a stock this dependable in December, 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 (December), its worst (October), and whether it really trades seasonally.
Yes, to a moderate degree. Since 2016 its best month (December, +4.7%) has run well ahead of its worst (October, −0.5%) — the heatmap above shows how steady that gap has been year to year.
December has been the strongest, averaging +4.7% and closing higher in 7 of 10 years since 2016.
It's the weakest, averaging −0.5% — 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