I call upon the collective genius of this forum once again with a "simple" question.

Why does the following statement not really return a blank cell?

=IF('Rapportage Sheet; Januari-Juni'!IJ4=0;"";'Rapportage Sheet; Januari-Juni'!IJ4)

Say I paste this formula in cell A1, and the referenced cell is empty, there appears to be no data in A1 (yay!). However if I check with =ISBLANK(A1) it returns "False". The reason this bugs me is because I have charts that are supposed to skip blank cells (the option "Plot empty cells as: Not plotted (leave gaps)" is enabled) but instead of leaving gaps it plots these cells as "0".

Is there a way to make a cell blank properly?

P.S.

=IF('Rapportage Sheet; Januari-Juni'!IJ4="";"";'Rapportage Sheet; Januari-Juni'!IJ4) returns the same results.