Can someone help me with the Excel formula to give the nearest ATM strike with a given underlying price and strike increment? Additionally, is this more processing intensive than simply creating a label row for option chain as ATM/ITM and OTM? =IF(A19<$A$2,"ITM",IF(A19=$A$2,"ATM","OTM")) Thank you.
I use this: =MROUND(D16*EXP(1)^(D19*(D20/365)),D21) where D16 = ex-dividend spot D19 = interest rate D20 = time to maturity (dte) D21 = strike difference