Put Option Rho
The change in a put option's price for a 1% increase in the risk-free interest rate.
What is Rho (Put)?
Rho (ρ) for a put option measures how much the put price changes when the risk-free rate rises by 1 percentage point. Put rho is always negative: higher rates increase the opportunity cost of holding a put and reduce the present value of the potential payoff, making puts less valuable. The effect is most significant for deep in-the-money puts and long-dated options.
Formula
Worked Example
Representative Q1 2024 market conditions
Source: Hull, J.C. — Options, Futures, and Other Derivatives, 11th ed., Ch. 19 (2024-01-15)
Calculate Rho (Put)
Current market price of the underlying stock
Option strike price
Annual risk-free rate
Time to expiration in years
Annualised implied volatility
Rho (per 1% rate)
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