Put-Call Ratio (Volume) (20-Day)

Put-Call Ratio (Volume): The ratio of puts traded to calls traded, for options with the relevant expiration date.

Ballard Power Systems, Inc. (BLDP) had 20-Day Put-Call Ratio (Volume) of 0.1443 for 2026-01-16.

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Figures for 2026-01-16

Volatility Metrics
Historical Volatility (Close-to-Close)	0.3666
Historical Volatility (Parkinson)	0.4159
Implied Volatility (Calls)	0.9115
Implied Volatility (Puts)	0.9395
Implied Volatility (Mean)	0.9255
Put-Call Implied Volatility Ratio	1.0307
Implied Volatility Skew	0.0891
Option Statistics
Put-Call Ratio (Volume)	0.1443
Put-Call Ratio (Open Interest)	0.0883