The takeaway
Tetra Tech Inc shows a pronounced seasonal pattern over 10 years of data — strongest in July (+5.2%) and softest in December (−3.7%).
Right now
In July, the stock has risen 90% of years, averaging +5.2%, about +3.1 pts better than the S&P 500.
The full picture
Tetra Tech Inc's most dependable month has been July, higher in 9 of 10 years; December has been its least reliable, up just 10% of the time.
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Month by month
The stock's clearest edge over the S&P 500 lands in May (+4.0 pts); it has trailed the market most in December (−4.7 pts).
“vs S&P” is Tetra Tech Inc’s average for a month minus the S&P 500’s average for that same month — isolating Tetra Tech Inc’s own seasonal edge from broad market drift.
Reality check
Over the last 5 years, July has closed higher 100% of the time versus 90% across the last 10 years — the pattern is strengthening.
Figures are the typical (median) July 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
This is a stock you can almost set a calendar by, and July is the anchor — it has closed higher in 9 of 10 Julys, the steadiest beat on its year.
The strength looks broad-based rather than freakish: its average (+5.2%) and median (+5.1%) sit close together, so no single blow-out year is flattering the figure. Few months are steadier: July's returns vary by just 4.1% year to year, and even its worst July in 10 years lost only 0.5% — the gentlest downside anywhere on its calendar. Better still, that strength is the stock's own and not just a buoyant market — July has outpaced the S&P 500 by +3.1 points on average. 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 stock's reliable season. The weaker half of the year is plainer: December has been the soft spot — the only month to average an outright loss (−3.7%), and the edge isn't year-round — the stock has trailed the S&P 500 in December, April, and March. Its roughest month on record was a −18.8% January in 2022 — a reminder of how hard even a seasonal name can fall.
July has now closed higher 6 years running. If anything it has sharpened recently — the last five Julys run ahead of the earlier years.
For a stock 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.
Short answers on the stock's best month (July), its worst (December), and whether it really trades seasonally.
Yes, to a pronounced degree. Since 2016 its best month (July, +5.2%) has run well ahead of its worst (December, −3.7%) — the heatmap above shows how steady that gap has been year to year.
July has been the strongest, averaging +5.2% and closing higher in 9 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.
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