The takeaway
Janus Henderson Short Duration Income ETF shows a slight seasonal lean over 10 years of data — strongest in May (+0.4%) and softest in March (0.0%).
Right now
In July, the fund has risen 100% of years, averaging +0.4%, roughly 1.8 pts behind the S&P 500.
The full picture
Janus Henderson Short Duration Income ETF's most dependable month has been May, higher in 9 of 9 years; March has been its least reliable, up just 56% of the time.
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| 2016 | — | — | — | — | — | — | — | — | — | — |
Month by month
The fund's clearest edge over the S&P 500 lands in January (+0.5 pts); it has trailed the market most in November (−2.1 pts).
“vs S&P” is Janus Henderson Short Duration Income ETF’s average for a month minus the S&P 500’s average for that same month — isolating Janus Henderson Short Duration Income ETF’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, May has closed higher 100% of the time versus 100% 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 all 9 Mays, but it heads a clutch of months that pull the year reliably upward.
Its average (+0.4%) and median (+0.4%) 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 0.2% spread), and even its worst May in 10 years lost only 0.1% — the gentlest downside anywhere on its calendar. Set against the S&P 500, mind, May is close to a wash — the gain mirrors the market more than it beats it. That consistency sets it apart from the field, where the average stock manages May only about 55% of the time.
The lift is near-universal — strength runs through almost every month of the year, not one window. On the other side of the ledger, March is the year's quietest corner, essentially flat on average, and the edge isn't year-round — the fund has trailed the S&P 500 in November, July, and April.
May has now closed higher 9 years running. 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 fund's months offer little reliable tilt.
Short answers on the fund's best month (May), its worst (March), and whether it really trades seasonally.
Only mildly. The fund's months are fairly even — May is the firmest (+0.4%) and March the softest (0.0%), a narrow spread that points to weak seasonality rather than a strong calendar effect.
May has been the strongest, averaging +0.4% and closing higher in all 9 years on record since 2016.
It's the weakest, averaging 0.0% — 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