SPRO (Spero Therapeutics, Inc. Common Stock)
Historical IV Rank & Volatility Regime
IV Rank measures where SPRO's current 30-day implied volatility sits in its trailing 90-day distribution (0% = lowest in 90 days, 100% = highest). It's the most reliable signal for whether options on SPRO are priced rich or cheap relative to its own recent regime.
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.
SPRO IV Rank Summary
Current
80%
Elevated — premium selling regime
30-Day Avg
50%
60-Day Avg
59%
90-Day Avg
54%
90-Day Low
15%
90-Day High
100%
IV Rank is bounded 0%–100% by construction. Sustained levels above 75% historically
precede mean reversion in SPRO's implied vol; sustained sub-25% readings
often coincide with low-realized regimes ahead of catalyst events. See the
Vol Arb Screener for symbols where current IV
rank diverges most from realized volatility.
SPRO IV Rank — Last 90 Trading Days
| Date | IV Rank | Avg IV |
|---|---|---|
| 20260923 | 80% | 4.9% |
| 20260922 | 68% | 4.3% |
| 20260921 | 83% | 5.0% |
| 20260918 | 77% | 4.7% |
| 20260917 | 82% | 5.0% |
| 20260916 | 73% | 4.5% |
| 20260915 | 64% | 4.1% |
| 20260914 | 76% | 4.7% |
| 20260911 | 68% | 4.3% |
| 20260910 | 70% | 4.4% |
| 20260909 | 77% | 4.7% |
| 20260908 | 76% | 4.7% |
| 20260904 | 56% | 3.8% |
| 20260903 | 62% | 4.0% |
| 20260902 | 41% | 3.0% |
| 20260901 | 19% | 1.7% |
| 20260831 | 42% | 2.9% |
| 20260828 | 15% | 1.5% |
| 20260827 | 31% | 2.3% |
| 20260826 | 30% | 2.2% |
| 20260825 | 29% | 2.2% |
| 20260824 | 23% | 1.9% |
| 20260821 | 25% | 2.0% |
| 20260820 | 35% | 2.5% |
| 20260819 | 37% | 2.6% |
| 20260818 | 26% | 2.1% |
| 20260817 | 35% | 2.5% |
| 20260814 | 33% | 2.4% |
| 20260813 | 35% | 2.5% |
| 20260812 | 23% | 1.9% |
| 20260811 | 26% | 2.1% |
| 20260810 | 21% | 1.8% |
| 20260806 | 15% | 1.5% |
| 20260805 | 65% | 4.0% |
| 20260804 | 63% | 3.9% |
| 20260803 | 100% | 5.8% |
| 20260731 | 100% | 5.4% |
| 20260730 | 70% | 3.8% |
| 20260729 | 95% | 4.9% |
| 20260728 | 100% | 5.2% |
| 20260727 | 100% | 4.7% |
| 20260724 | 100% | 4.5% |
| 20260723 | 100% | 4.4% |
| 20260722 | 100% | 4.4% |
| 20260721 | 100% | 4.0% |
| 20260720 | 100% | 3.6% |
| 20260716 | 100% | 3.3% |
| 20260715 | 88% | 3.0% |
| 20260714 | 87% | 2.9% |
| 20260713 | 49% | 2.0% |
| 20260710 | 21% | 1.3% |
| 20260709 | 47% | 1.9% |
| 20260708 | 44% | 1.9% |
| 20260707 | 52% | 2.0% |
| 20260706 | 47% | 1.9% |
| 20260702 | 28% | 1.5% |
| 20260701 | 63% | 2.3% |
| 20260630 | 55% | 2.1% |
| 20260629 | 59% | 2.2% |
| 20260626 | 69% | 2.5% |
| 20260625 | 62% | 2.3% |
| 20260624 | 53% | 2.1% |
| 20260623 | 58% | 2.2% |
| 20260622 | 54% | 2.1% |
| 20260618 | 40% | 1.7% |
| 20260617 | 55% | 2.1% |
| 20260616 | 36% | 1.6% |
| 20260615 | 37% | 1.7% |
| 20260613 | 51% | 2.0% |
| 20260612 | 53% | 2.1% |
| 20260611 | 49% | 2.0% |
| 20260610 | 45% | 1.9% |
| 20260609 | 39% | 1.7% |
| 20260608 | 48% | 2.0% |
| 20260605 | 38% | 1.7% |
| 20260604 | 44% | 1.8% |
| 20260603 | 33% | 1.4% |
| 20260602 | 49% | 1.9% |
| 20260601 | 64% | 2.3% |
| 20260529 | 47% | 1.8% |
| 20260528 | 22% | 1.2% |
| 20260527 | 46% | 1.8% |
| 20260526 | 49% | 1.9% |
| 20260510 | 40% | 1.6% |
| 20260508 | 39% | 1.6% |
| 20260507 | 23% | 1.2% |
| 20260506 | 32% | 1.4% |
| 20260505 | 38% | 1.6% |
| 20260504 | 25% | 1.2% |
| 20260502 | 52% | 2.0% |