What is the best way to calculate daily decay of a bought Option?
Specially on Options on Futures contracts like Es/ YM etc
( Not stock option, Since the underlying is a futures contract there is no dividend)
so if a 90 day ATM expiry option is say 90 points does that mean it will decay 1 point each day or the decay will be at as smaller rate initially and increases suddenly in last few days? assume that VOL has not changed