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.

Zai Lab Limited Unsponsored ADR (ZLAB) had 20-Day Put-Call Ratio (Open Interest) of 0.0200 for 2026-01-16.

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Figures for 2026-01-16

Volatility Metrics
Historical Volatility (Close-to-Close)	0.4466
Historical Volatility (Parkinson)	0.3073
Implied Volatility (Calls)	0.7443
Implied Volatility (Puts)	0.6502
Implied Volatility (Mean)	0.6972
Put-Call Implied Volatility Ratio	0.8736
Implied Volatility Skew	0.2376
Option Statistics
Put-Call Ratio (Volume)	0.0000
Put-Call Ratio (Open Interest)	0.0200