ACI implied volatility
From the closing options book · October 20, 2026 · updated after every close
ACI's at-the-money implied volatility was 43.5% at the October 20, 2026 close. Over the past 24 sessions it ranged from 31.6% to 85.7%, putting today's level at an IV rank of 22 and IV percentile of 50.
ACI at-the-money IV, last 60 sessions
Options were pricing more movement than ACI actually delivered over the last 20 sessions (43.5% implied against 32.0% realized).
IV rank places today's IV between the period's low (0) and high (100); IV percentile is the share of sessions with lower IV. Both use ACI's own closing history.
These are the October 20, 2026 closing numbers. Members see ACI's map move live all session.
Common questions
43.5% at the money at the October 20, 2026 close.
22 over the past 24 sessions (IV percentile 50).
Its IV percentile is 50: middling against its own past year.
Compare: implied volatility on other tickers
Measured from the closing options book and rebuilt after every close. Nothing on this page is live. Levels are where dealer hedging is concentrated, not targets or forecasts. Not investment advice.