IV Percentile
Percent of sessions in the lookback window whose constant-maturity ATM IV was strictly below today's (0–100). Distinct from IV Rank.
IV Percentile
Definition
Percent of sessions in the lookback window whose constant-maturity ATM IV was strictly below today's (0–100). Distinct from IV Rank.
Parameters
Asset, Lookback period (default 252 days)
Output range: 0–100
Example
`IVPercentile(QQQ, 252) < 20` (IV lower than on 80% of the past year)
Usage notes
IV Percentile answers 'how often was IV lower?'; IV Rank answers 'where is IV in its high-low range?'. Ship both — they disagree near spikes.
Full indicator reference