BMRN·BioMarin Pharmaceutical Inc.

Realized volatility (21d)

23.8% 17th pct

Below its peak

-63.0%

vs 200-day average

-5.9%

Up days (1y)

46%

BioMarin Pharmaceutical Inc. is currently running 23.8% annualised volatility over the last 21 sessions. Measured against BMRN's own 13 years of daily returns rather than a market-wide average, that is the 17th percentile — unusually subdued by its own history, against a typical reading of 32.1%. 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.

BMRN is trading -63.0% below its running peak. Across 12 full years on file, its median worst-drawdown-in-a-year was -34.1%, and the deepest was -44.9% in 2020. The current drawdown is already deeper than this stock's typical annual low point, which puts it in the part of its range where past recoveries began — and where past declines also continued.

Price sits -5.9% from its 200-day moving average. Against every other day in its history, that gap ranks at the 35th percentile — close to the gap it normally carries. Over the past year BMRN closed higher on 46% of sessions, and it is currently 1 session into a rising streak.

On October specifically: over 14 years of records, BMRN finished the month higher 4 of 14 times, with a median return of -4.0% and an average of -1.5%. Its strongest month historically has been November at +5.4% on average, its weakest September at -6.1%. 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: BMRN has opened more than 2% away from the prior close in 199 of 3,267 sessions (6.1% of the time), with the largest gaps running +9.3% and -10.5%. For anyone holding through an event, that rate is a better guide to overnight exposure than the intraday range.

All figures computed from 3,268 daily closes between 2013-10-15 and 2026-10-14, split-adjusted, recomputed daily. Percentiles are against BMRN's own 13-year history, not a peer group or index.