- An interest rate compounded continuously that will be noted as r.
- Geometric Brownian motion dynamics for equity price that will be noted with St
- The equity is paying a dividend noted with c.
- The maturity and the strike are noted with T and K respectively.
The formula for the Black & Scholes pricing model for an European call option is:
Given the put-call parity between the options' prices, the formula for the European put option is:
To apply these formulae in Excel, do the following:
- Specify the option's parameters: the spot price of the underlying security, the maturity of the option, the dividend yield of the underlying and its volatility, the rate of the option and its strike.
- Input the formulae for the two discount factors as follows: For the first discount factor, add the displayed in this screenshot, adjusted to your spreadsheet:
- Input the formula shown in the following figure:
For the second discount factor, input the formula used in the next screenshot:
You can now calculate the price of the option.
That's about it! You now know how to use this pricing model in an Excel spreadsheet. If you have any questions, don't hesitate to contact me by writing a comment on this page.
See you at the next tutorial!