The takeaway
Byline Bancorp Inc shows a moderate seasonal pattern over 9 years of data — strongest in June (+1.7%) and softest in September (−2.9%).
Right now
In July, the stock has risen 67% of years, averaging +4.9%, about +2.7 pts better than the S&P 500.
The full picture
Byline Bancorp Inc's most dependable month has been June, higher in 6 of 8 years; September has been its least reliable, up just 22% of the time.
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| 2017 | — | — | — | — | — | — |
Month by month
The stock's clearest edge over the S&P 500 lands in February (+2.8 pts); it has trailed the market most in March (−9.3 pts).
“vs S&P” is Byline Bancorp Inc’s average for a month minus the S&P 500’s average for that same month — isolating Byline Bancorp Inc’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, June has closed higher 60% of the time versus 75% across the last 9 years — the pattern is weakening.
Figures are the typical (median) June return and how often it rose — the last 5 years versus the last 9(the heatmap’s default window). This verdict stays anchored to that 9-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. June stands out, higher in 6 of 8 Junes, but it heads a clutch of months that pull the year reliably upward.
Its average (+1.7%) and median (+2.0%) land within a hair of each other — the tell of steady, year-after-year gains rather than one outlier doing the work. It is also the calendar's calmest month, its returns swinging least from year to year (a 4.0% spread), and even its worst June in 9 years lost only 4.6% — the gentlest downside anywhere on its calendar. Crucially, the gain is the stock's own rather than a rising tide's: June has cleared the S&P 500 by +1.4 points above the index. That consistency sets it apart from the field, where the average stock manages June only about 52% of the time.
The strength clusters rather than stands alone — May–August forms a firm stretch that carries much of the year. On the other side of the ledger, September has been the soft spot — the weakest of 2 months that average a loss (−2.9%), and the edge isn't year-round — the stock has trailed the S&P 500 in March and September. Its roughest month on record was a −41.5% March in 2020 — a reminder of how hard even a seasonal name can fall.
The pattern has softened of late, June's last five years slipping below its longer-run record.
The takeaway is less about when to buy than what to expect: June aside, the stock's months offer little reliable tilt. With a short 9-year record, the signal is best held loosely.
Short answers on the stock's best month (June), its worst (September), and whether it really trades seasonally.
Yes, to a moderate degree. Since 2017 its best month (June, +1.7%) has run well ahead of its worst (September, −2.9%) — the heatmap above shows how steady that gap has been year to year.
June has been the strongest, averaging +1.7% and closing higher in 6 of 8 years since 2017.
It's the weakest, averaging −2.9% — 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