HALO·Halozyme Therapeutics Inc.

Realized volatility (21d)

35.5% 32nd pct

Below its peak

0.0%

vs 200-day average

+46.2%

Up days (1y)

49%

Halozyme Therapeutics Inc. is currently running 35.5% annualised volatility over the last 21 sessions. Measured against HALO's own 13 years of daily returns rather than a market-wide average, that is the 32nd percentile — on the quiet side for this stock, against a typical reading of 42.0%. 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.

HALO is at its running peak. Across 12 full years on file its median worst-drawdown-in-a-year was -35.5%, with the deepest at -60.0% in 2014 — so highs have historically been given back before they were extended.

Price sits +46.2% from its 200-day moving average. Against every other day in its history, that gap ranks at the 94th percentile — a wider gap than this stock usually carries. Over the past year HALO closed higher on 49% of sessions, and it is currently 1 session into a rising streak.

On October specifically: over 14 years of records, HALO finished the month higher 7 of 14 times, with a median return of +1.1% and an average of -1.7%. Its strongest month historically has been November at +10.6% on average, its weakest March at -3.5%. 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: HALO has opened more than 2% away from the prior close in 383 of 3,268 sessions (11.7% of the time), with the largest gaps running +16.7% and -11.8%. For anyone holding through an event, that rate is a better guide to overnight exposure than the intraday range.

All figures computed from 3,269 daily closes between 2013-10-15 and 2026-10-14, split-adjusted, recomputed daily. Percentiles are against HALO's own 13-year history, not a peer group or index.