Put-Call Ratio (Open Interest) (90-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.

Proto Labs, Inc. (PRLB) had 90-Day Put-Call Ratio (Open Interest) of 0.1866 for 2026-05-21.

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Figures for 2026-05-21

Volatility Metrics
Historical Volatility (Close-to-Close)	0.3600
Historical Volatility (Parkinson)	0.3991
Implied Volatility (Calls)	0.3969
Implied Volatility (Puts)	0.4220
Implied Volatility (Mean)	0.4094
Put-Call Implied Volatility Ratio	1.0632
Implied Volatility Skew	0.0152
Option Statistics
Put-Call Ratio (Volume)	--
Put-Call Ratio (Open Interest)	0.1866