The takeaway
Capital Southwest Corporation shows a slight seasonal lean over 10 years of data — strongest in August (+2.5%) and softest in September (−0.2%).
Right now
In July, the stock has risen 50% of years, averaging +1.8% — essentially in line with the S&P 500.
The full picture
Capital Southwest Corporation's most dependable month has been August, higher in 7 of 10 years; September 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 April (+3.1 pts); it has trailed the market most in March (−3.6 pts).
“vs S&P” is Capital Southwest Corporation’s average for a month minus the S&P 500’s average for that same month — isolating Capital Southwest Corporation’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, August has closed higher 60% of the time versus 70% across the last 10 years — the pattern is holding.
Figures are the typical (median) August 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 August is the anchor — it has closed higher in 7 of 10 Augusts, the steadiest beat on its year.
The strength looks broad-based rather than freakish: its average (+2.5%) and median (+2.2%) sit close together, so no single blow-out year is flattering the figure. Few months are steadier: August's returns vary by just 3.7% year to year. Better still, that strength is the stock's own and not just a buoyant market — August has outpaced the S&P 500 by +2.2 points on average. Few peers keep such company in August — the typical stock clears it just 52% of the time.
It doesn't stand entirely alone — January, April, and May have leaned firm as well, if less emphatically. The weaker half of the year is plainer: September 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 March and October. Its roughest month on record was a −37.4% March in 2020 — 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.
For a stock this dependable in August, 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 (August), its worst (September), and whether it really trades seasonally.
Only mildly. The stock's months are fairly even — August is the firmest (+2.5%) and September the softest (−0.2%), a narrow spread that points to weak seasonality rather than a strong calendar effect.
August has been the strongest, averaging +2.5% and closing higher in 7 of 10 years since 2016.
It's the weakest, averaging −0.2% — 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