Black's model for pricing options on futures and forwards is as follows: 

OV = option value. F = forward price of the underlying asset with a maturity equal to the option's maturity date. X = exercise price (strike). r = riskfree interest rate, expressed with continuous compounding. vol = volatility of the relative price change of the underlying asset. T = time to maturity measured in years (actual/365 basis). N(.) = cumulative normal distribution of (.). iPC = 1 for call / 1 for put. 

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