I am trying to make a cell value be null with the
following:=IF($C$2=A18,A18,"")

My goal is to make C18 be empty if this is false. I don't want it to be
blank; I want it to be as if I never typed a value in the cell at all.

When I try the above, C18 is blank when the above evaluates to false, but I
am creating a chart and the chart recognizes the cell as having a value. It
plots the data point. I've already gone to Tools/Options/Chart and set it to
not plot empty cells. The problem is that it still shows the x-axis value
though with no data. If I delete the contents of C18, then the chart comes
out right, but that also means, there is no equation in there to fill the
cell when the above equation is true.

Is there a way to either make C18 truly empty based on the condition above
or make the chart behave and "really" not plot blank cells?

thank you in advance.