I am creating a worksheet where fields are updated dynamically using a dde,
once the result of a formula is calculated it brings about a certain
condition in one other part of the sheet example:

IF(AI91="LONG","L",IF(AJ91="SHORT","S",""))

Since the fields that this formula observes are dynamically updated the
condition might change, but since I am only interested in the first occurance
i wanted to lock the result of the first time a calculation is done, is it
possibile?