Create a named range, call it Strike
in the 'refrs to' box enter =GET.CELL(23,INDIRECT("RC[-1]",0))
Then use the formula
=IF(Strike,1,0)
Note that this assumes the cell with the strikethru text will be to the immediate left of the formula.
works thru cell strike/un-strike without F9 refresh needed
Are you sure it works without a recalculation ?!!!!