DGX·Quest Diagnostics Incorporated

Realized volatility (21d)

31.0% 90th pct

Below its peak

-5.7%

vs 200-day average

+12.3%

Up days (1y)

49%

Quest Diagnostics Incorporated is currently running 31.0% annualised volatility over the last 21 sessions. Measured against DGX's own 13 years of daily returns rather than a market-wide average, that is the 90th percentile — elevated for this stock, against a typical reading of 19.5%. 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.

DGX is trading -5.7% below its running peak. Across 12 full years on file, its median worst-drawdown-in-a-year was -16.9%, and the deepest was -39.3% in 2020. 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 +12.3% from its 200-day moving average. Against every other day in its history, that gap ranks at the 83rd percentile — a wider gap than this stock usually carries. Over the past year DGX closed higher on 49% of sessions, and it is currently 1 session into a rising streak.

On October specifically: over 14 years of records, DGX finished the month higher 10 of 14 times, with a median return of +1.7% and an average of +2.1%. Its strongest month historically has been April at +4.1% on average, its weakest September at -1.8%. 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: DGX has opened more than 2% away from the prior close in 72 of 3,268 sessions (2.2% of the time), with the largest gaps running +6.4% and -9.9%. 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, DGX moved an average of 1.5% in the session after earnings, closing higher 2 of those 3 times, with a median move of +0.2% and a largest of -2.5%.

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