Chart.DisplayBlanksAs (PowerPoint)

Returns or sets the way that blank cells are plotted on a chart. Can be one of the XlDisplayBlanksAs constants. Possible return values are xlInterpolated - Values are interpolated into the chart, xlNotPlotted - Blank cells are not plotted, xlZero - Blanks are plotted as zero.

ActivePresentation.Slides(1).Shapes(1).Chart.DisplayBlanksAs = xlInterpolated