The takeaway
iShares Micro-Cap ETF shows a pronounced seasonal pattern over 10 years of data — strongest in November (+5.0%) and softest in March (−3.7%).
Right now
In July, the fund has risen 60% of years, averaging +2.4% — essentially in line with the S&P 500.
The full picture
iShares Micro-Cap ETF's most dependable month has been November, higher in 7 of 10 years; March has been its least reliable, up just 40% of the time.
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Month by month
The fund's clearest edge over the S&P 500 lands in November (+2.7 pts); it has trailed the market most in March (−4.7 pts).
“vs S&P” is iShares Micro-Cap ETF’s average for a month minus the S&P 500’s average for that same month — isolating iShares Micro-Cap ETF’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, November has closed higher 60% of the time versus 70% across the last 10 years — the pattern is holding.
Figures are the typical (median) November 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. November stands out, higher in 7 of 10 Novembers, but it heads a clutch of months that pull the year reliably upward.
A typical November brings +3.3%, a shade under the +5.0% average. Crucially, the gain is the fund's own rather than a rising tide's: November has cleared the S&P 500 by +2.7 points above the index. Some of that is a strong month market-wide, mind — November rises for about 62% of stocks — so the tendency is real if not unique.
A few other months pull their weight: May, June, and July have also closed higher more often than not. At the other end of the calendar, March has been the soft spot — the weakest of 2 months that average a loss (−3.7%), and the edge isn't year-round — the fund has trailed the S&P 500 in March, October, and April. Its roughest month on record was a −25.6% 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.
The takeaway is less about when to buy than what to expect: November aside, the fund's months offer little reliable tilt.
Short answers on the fund's best month (November), its worst (March), and whether it really trades seasonally.
Yes, to a pronounced degree. Since 2016 its best month (November, +5.0%) has run well ahead of its worst (March, −3.7%) — the heatmap above shows how steady that gap has been year to year.
November has been the strongest, averaging +5.0% and closing higher in 7 of 10 years since 2016.
It's the weakest, averaging −3.7% — 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