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.

TransAlta Corporation (TAC) had 20-Day Put-Call Ratio (Open Interest) of 0.0743 for 2026-01-16.

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Figures for 2026-01-16

Volatility Metrics
Historical Volatility (Close-to-Close)	0.2596
Historical Volatility (Parkinson)	0.2759
Implied Volatility (Calls)	0.5450
Implied Volatility (Puts)	0.5097
Implied Volatility (Mean)	0.5274
Put-Call Implied Volatility Ratio	0.9352
Implied Volatility Skew	--
Option Statistics
Put-Call Ratio (Volume)	0.3527
Put-Call Ratio (Open Interest)	0.0743