OTTR · IV Rank History

Otter Tail Corp

IV rank shows where OTTR's implied volatility sits within its own recent range: 0 is the lowest reading in the window, 100 the highest. This page gives the 52-week version, the 90-session version our screeners use, the IV percentile, and the daily history.

OTTR's 30-day at-the-money implied volatility was 31.8% as of Oct 26, 2026. Its 52-week IV rank is 77 and its IV percentile is 95%: IV was lower on 95% of the past year's sessions. Over those 52 weeks it ranged from 16.4% (May 12, 2026) to 36.5% (Oct 30, 2025). On the 90-session window our screeners use, the IV rank is 100.

OTTR IV rank history

504 sessions

Filled line: 90-session IV rank (0–100, left axis). Dashed line: 30-day at-the-money implied volatility (right axis).

OTTR IV rank and implied volatility as of 2026-10-26

52-Week IV Rank
77
0 = year low, 100 = year high
IV Percentile
95%
of past-year sessions had lower IV
90-Session IV Rank
100
used by our screeners
30-Day ATM IV
31.8%
1-year average 26.4%
52-Week IV High
36.5%
2025-10-30
52-Week IV Low
16.4%
2026-05-12
History Since
2023-05-02
849 sessions

How these are measured. Implied volatility here is OTTR's 30-day at-the-money IV: the implied volatility of the calls and puts struck nearest the share price, blended between the expirations on either side of 30 days so every reading covers the same horizon. It's the IV level options traders usually quote, and it doesn't jump when the nearest expiration rolls from a weekly to a monthly. The 7-day figure is the same measure a week out, so it reacts first to near-term events such as earnings.

52-week IV rank = (today's IV − 52-week low) ÷ (52-week high − 52-week low) × 100. IV percentile is the share of the past year's sessions that closed with lower IV than today. The 90-session IV rank applies the same rank formula to the last 90 sessions, so it reacts faster.

A high reading means OTTR options are expensive relative to their own recent history, which is common ahead of earnings or after a sharp move. It says nothing about which way the stock will go. The Vol Arb Screener ranks every tracked symbol by these measures.

OTTR implied volatility by month

MonthAvg ATM IVHighLowAvg IV Rank (90-session)
Oct 2026 (to date) 28.2% 31.8% 25.4% 72
Sep 2026 24.7% 29.1% 21.7% 52
Aug 2026 21.7% 29.4% 19.2% 31
Jul 2026 28.8% 31.7% 26.0% 72
Jun 2026 25.3% 29.5% 20.0% 50
May 2026 25.1% 29.1% 16.4% 43
Apr 2026 29.4% 33.6% 26.1% 66
Mar 2026 25.7% 31.1% 21.1% 39
Feb 2026 28.5% 34.5% 23.2% 53
Jan 2026 27.4% 30.8% 25.0% 46
Dec 2025 25.1% 33.0% 19.6% 32
Nov 2025 24.9% 33.3% 21.6% 30
Oct 2025 31.9% 36.5% 27.3% 64
Sep 2025 24.7% 27.9% 22.4% 25
Aug 2025 24.9% 30.9% 19.9% 13
Jul 2025 32.2% 37.3% 29.2% 38
Jun 2025 27.0% 39.0% 23.1% 16
May 2025 28.5% 36.8% 23.9% 11
Apr 2025 40.0% 47.4% 30.8% 68
Mar 2025 31.9% 35.5% 27.3% 39
Feb 2025 31.9% 40.2% 27.8% 40
Jan 2025 33.6% 37.1% 30.4% 56
Dec 2024 32.0% 34.5% 27.1% 39
Nov 2024 30.7% 39.0% 26.6% 27
Oct 2024 37.1% 39.3% 34.8% 76
Sep 2024 33.1% 36.3% 30.6% 58
Aug 2024 31.3% 41.0% 27.3% 48
Jul 2024 31.1% 34.3% 27.7% 47
Jun 2024 28.5% 31.6% 24.5% 34
May 2024 27.6% 35.2% 22.1% 31
Apr 2024 34.8% 41.1% 30.0% 78
Mar 2024 28.6% 33.1% 24.1% 48
Feb 2024 31.2% 38.7% 23.0% 52
Jan 2024 31.9% 36.9% 26.5% 55
Dec 2023 25.7% 30.0% 17.7% 31
Nov 2023 28.8% 37.1% 23.7% 43
Oct 2023 37.4% 43.8% 31.5% 85
Sep 2023 28.5% 35.4% 21.2% 58
Aug 2023 24.4% 32.6% 17.6% 27
Jul 2023 29.9% 36.5% 23.8% 62
Jun 2023 27.5% 33.3% 22.3% 49
May 2023 27.2% 32.5% 23.7% 66

OTTR IV rank: last 30 sessions

DateIV Rank (90-session)30-Day ATM IV7-Day ATM IV
2026-10-26 100 31.8% —
2026-10-23 67 27.6% —
2026-10-22 78 29.0% —
2026-10-21 86 29.9% —
2026-10-20 76 28.7% —
2026-10-19 80 29.2% —
2026-10-16 55 26.0% —
2026-10-15 56 26.1% —
2026-10-14 78 28.9% 44.8%
2026-10-13 69 27.8% 33.0%
2026-10-12 73 28.4% 30.3%
2026-10-09 79 29.1% 27.7%
2026-10-08 73 28.3% 29.1%
2026-10-07 66 27.5% 30.1%
2026-10-06 75 28.6% 28.9%
2026-10-05 73 28.3% 32.8%
2026-10-02 49 25.4% 25.3%
2026-10-01 60 26.7% 26.6%
2026-09-30 79 29.1% 32.4%
2026-09-29 64 27.2% 30.4%
2026-09-28 65 27.3% 29.5%
2026-09-25 68 27.7% 30.0%
2026-09-24 67 27.6% —
2026-09-23 58 26.5% —
2026-09-22 50 25.4% —
2026-09-21 48 23.8% —
2026-09-18 34 21.7% —
2026-09-17 60 25.6% —
2026-09-16 60 25.5% 49.9%
2026-09-15 53 24.4% 35.1%

Market data may be delayed, incomplete, or inaccurate. Not a recommendation to buy, sell, or hold any security. Verify quotes with your broker before trading. See Terms §17.