The takeaway
Harbor Long-Term Growers ETF shows a pronounced seasonal pattern over 4 years of data — strongest in January (+6.9%) and softest in December (−1.6%).
Right now
In July, the fund has risen 75% of years, averaging +3.8%, about +1.7 pts better than the S&P 500.
The full picture
Harbor Long-Term Growers ETF's most dependable month has been January, higher in 3 of 3 years; December has been its least reliable, up just 25% of the time.
| Year | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Win rate % | ||||||||||||
| Median return % | ||||||||||||
| 2025 | ||||||||||||
| 2024 | ||||||||||||
| 2023 | ||||||||||||
| 2022 | — |
Month by month
The fund's clearest edge over the S&P 500 lands in January (+7.1 pts); it has trailed the market most in April (−5.7 pts).
“vs S&P” is Harbor Long-Term Growers ETF’s average for a month minus the S&P 500’s average for that same month — isolating Harbor Long-Term Growers ETF’s own seasonal edge from broad market drift.
Reality check
Over the last 3 years, January has closed higher 100% of the time versus 100% across the last 4 years — the pattern is holding.
Figures are the typical (median) January return and how often it rose — the last 3 years versus the last 4(the heatmap’s default window). This verdict stays anchored to that 4-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 January is the anchor — it has closed higher in all 3 Januaries, the steadiest beat on its year.
The strength looks broad-based rather than freakish: its average (+6.9%) and median (+6.3%) sit close together, so no single blow-out year is flattering the figure. Few months are steadier: January's returns vary by just 3.6% year to year, and even its worst January in 4 years lost only 2.8% — the gentlest downside anywhere on its calendar. Better still, that strength is the fund's own and not just a buoyant market — January has outpaced the S&P 500 by +7.1 points on average. Few peers keep such company in January — the typical stock clears it just 53% of the time.
It doesn't stand entirely alone — May, June, and July have leaned firm as well, if less emphatically. On the other side of the ledger, December has been the soft spot — the weakest of 3 months that average a loss (−1.6%), and the edge isn't year-round — the fund has trailed the S&P 500 in April, December, and September. Its roughest month on record was a −14.8% April in 2022 — a reminder of how hard even a seasonal name can fall.
For a fund this dependable in January, the sharper question is the rest of the year — outside its strong stretch, the calendar gives far less to lean on. With a short 4-year record, the signal is best held loosely.
Short answers on the fund's best month (January), its worst (December), and whether it really trades seasonally.
Yes, to a pronounced degree. Since 2022 its best month (January, +6.9%) has run well ahead of its worst (December, −1.6%) — the heatmap above shows how steady that gap has been year to year.
January has been the strongest, averaging +6.9% and closing higher in all 3 years on record since 2022.
It's the weakest, averaging −1.6% — 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