The takeaway
iShares iBonds Dec 2027 Term Corporate ETF shows a slight seasonal lean over 9 years of data — strongest in July (+1.0%) and softest in September (−0.5%).
Right now
In July, the fund has risen 100% of years, averaging +1.0%, roughly 1.1 pts behind the S&P 500.
The full picture
iShares iBonds Dec 2027 Term Corporate ETF's most dependable month has been July, higher in 8 of 8 years; September has been its least reliable, up just 22% of the time.
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| 2017 | — | — | — | — | — | — | — | — |
Month by month
The fund's clearest edge over the S&P 500 lands in January (+0.8 pts); it has trailed the market most in March (−1.9 pts).
“vs S&P” is iShares iBonds Dec 2027 Term Corporate ETF’s average for a month minus the S&P 500’s average for that same month — isolating iShares iBonds Dec 2027 Term Corporate ETF’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, July has closed higher 100% of the time versus 100% across the last 9 years — the pattern is holding.
Figures are the typical (median) July 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
This is a fund you can almost set a calendar by, and July is the anchor — it has closed higher in all 8 Julys, the steadiest beat on its year.
The strength looks broad-based rather than freakish: its average (+1.0%) and median (+1.0%) sit close together, so no single blow-out year is flattering the figure. No month is steadier: July's returns vary by just 0.7% year to year, and even its worst July in 9 years lost only 0.2% — the gentlest downside anywhere on its calendar. Few peers keep such company in July — the typical stock clears it just 61% of the time.
July anchors a run, too: the May-through-August window has been the fund's reliable season. On the other side of the ledger, September has been the soft spot — the weakest of 3 months that average a loss (−0.5%), and the edge isn't year-round — the fund has trailed the S&P 500 in March, November, and October.
July has now closed higher 8 years running. Reassuringly, the tendency has held its shape: the recent five years still track the years behind them.
For a fund this dependable in July, the sharper question is the rest of the year — outside its strong stretch, the calendar gives far less to lean on. With a short 9-year record, the signal is best held loosely.
Short answers on the fund's best month (July), its worst (September), and whether it really trades seasonally.
Only mildly. The fund's months are fairly even — July is the firmest (+1.0%) and September the softest (−0.5%), a narrow spread that points to weak seasonality rather than a strong calendar effect.
July has been the strongest, averaging +1.0% and closing higher in all 8 years on record since 2017.
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