Black–Scholes Pricing for FX

The FE-635 workbook implements Black–Scholes-style pricing for calls, puts, forwards, and deposits. Its inputs separate the domestic discount rate from the foreign rate, because an FX option has two money-market accounts in the carry relationship.

The spreadsheet's maturity convention is explicit: \(T=\text{Days}/365\). The pricing routine then consumes forward or strike, domestic and foreign rates, and volatility. That separation is more important than the function name; passing spot where the workbook expects forward FX changes the result systematically.

The notes treat the implementation as a practitioner tool. It is a compact expression of the assumptions, not a substitute for checking quote direction, settlement, and discounting currency.