Historical Volatility (Parkinson) (60-Day)

Historical Volatility (Parkinson): The past volatility of the security over the selected time frame, calculated using the high and low prices on each trading day.

AECOM (ACM) had 60-Day Historical Volatility (Parkinson) of 0.3528 for 2026-09-04.

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Over 300 data fields encompassing historical volatility, implied volatility, and put-call ratios for multiple time frames
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Figures for 2026-09-04

Volatility Metrics
Historical Volatility (Close-to-Close)	0.4676
Historical Volatility (Parkinson)	0.3528
Implied Volatility (Calls)	0.3690
Implied Volatility (Puts)	0.3724
Implied Volatility (Mean)	0.3707
Put-Call Implied Volatility Ratio	1.0093
Implied Volatility Skew	-0.0075
Option Statistics
Put-Call Ratio (Volume)	1.0952
Put-Call Ratio (Open Interest)	0.9647