The takeaway
iShares Core MSCI International Developed Market shows a moderate seasonal pattern over 9 years of data — strongest in November (+3.1%) and softest in June (−0.4%).
Right now
In July, the fund has risen 78% of years, averaging +1.6%, roughly 0.5 pts behind the S&P 500.
The full picture
iShares Core MSCI International Developed Market's most dependable month has been November, higher in 7 of 9 years; June has been its least reliable, up just 44% of the time.
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| 2017 | — | — |
Month by month
The fund's clearest edge over the S&P 500 lands in January (+2.2 pts); it has trailed the market most in March (−1.8 pts).
“vs S&P” is iShares Core MSCI International Developed Market’s average for a month minus the S&P 500’s average for that same month — isolating iShares Core MSCI International Developed Market’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, November has closed higher 80% of the time versus 78% across the last 9 years — the pattern is holding.
Figures are the typical (median) November 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
The seasonal story is really one month's story — November. It has closed higher in 7 of 9 Novembers, a concentration the rest of the calendar can't touch.
Read it with one caveat: the average (+3.1%) runs well ahead of the median (+0.7%), so a handful of outsized years — not steady strength — do much of the lifting. Better still, that strength is the fund's own and not just a buoyant market — November has outpaced the S&P 500 by +0.7 points on average. Few peers keep such company in November — the typical stock clears it just 62% of the time.
November anchors a run, too: the November-through-January window has been the fund's reliable season. On the other side of the ledger, June 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 March, October, and February. Its roughest month on record was a −16.6% 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 fund this dependable in November, 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 (November), its worst (June), and whether it really trades seasonally.
Yes, to a moderate degree. Since 2017 its best month (November, +3.1%) has run well ahead of its worst (June, −0.4%) — the heatmap above shows how steady that gap has been year to year.
November has been the strongest, averaging +3.1% and closing higher in 7 of 9 years since 2017.
It's the weakest, averaging −0.4% — 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