Put-Call Ratio (Open Interest) (20-Day)

Put-Call Ratio (Open Interest): The ratio of outstanding put contracts to outstanding call contracts at the close of the trading day, for options with the relevant expiration date.

Summit Therapeutics PLC (SMMT) had 20-Day Put-Call Ratio (Open Interest) of 1.0024 for 2026-04-21.

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Figures for 2026-04-21

Volatility Metrics
Historical Volatility (Close-to-Close)	0.6815
Historical Volatility (Parkinson)	0.7435
Implied Volatility (Calls)	1.0752
Implied Volatility (Puts)	1.0985
Implied Volatility (Mean)	1.0868
Put-Call Implied Volatility Ratio	1.0217
Implied Volatility Skew	0.0098
Option Statistics
Put-Call Ratio (Volume)	0.1541
Put-Call Ratio (Open Interest)	1.0024