GH·Guardant Health Inc

Realized volatility (21d)

49.9% 33rd pct

Below its peak

-9.7%

vs 200-day average

+32.8%

Up days (1y)

55%

Guardant Health Inc is currently running 49.9% annualised volatility over the last 21 sessions. Measured against GH's own 8 years of daily returns rather than a market-wide average, that is the 33rd percentile — on the quiet side for this stock, against a typical reading of 59.4%. The distinction matters because a number that looks calm for one stock is turbulent for another, and the absolute figure on its own tells you neither.

GH is trading -9.7% below its running peak. Across 7 full years on file, its median worst-drawdown-in-a-year was -45.9%, and the deepest was -75.6% in 2022. The current pullback is therefore shallower than what this stock gives back in a typical year, which is context worth having before treating it as a dislocation.

Price sits +32.8% from its 200-day moving average. Against every other day in its history, that gap ranks at the 76th percentile — a somewhat wider gap than its own norm. Over the past year GH closed higher on 55% of sessions, and it is currently 1 session into a rising streak.

On October specifically: over 9 years of records, GH finished the month higher 4 of 9 times, with a median return of -1.1% and an average of +5.4%. Its strongest month historically has been May at +12.9% on average, its weakest December at -8.3%. Seasonality is a weak signal on its own — a decade is a small sample and regimes change — but it is a real distribution rather than a rule of thumb.

Overnight risk is measurable too: GH has opened more than 2% away from the prior close in 327 of 2,016 sessions (16.2% of the time), with the largest gaps running +11.9% and -15.6%. For anyone holding through an event, that rate is a better guide to overnight exposure than the intraday range.

Across the last 3 dated reports on file, GH moved an average of 2.6% in the session after earnings, closing higher 1 of those 3 times, with a median move of -0.3% and a largest of -6.6%.

All figures computed from 2,017 daily closes between 2018-10-04 and 2026-10-14, split-adjusted, recomputed daily. Percentiles are against GH's own 8-year history, not a peer group or index.