TDataLabel.PositionZeroBased Property
Coordinates in percent of the chart area. Different from PositionXls this value has no margin attached. In old xls files, this value might not be set. If set, it should always be used instead of PositionXls. Note that for titles and axis titles the height and width is always automatic. For data labels in xlsx files, you can specify a size.
Syntax
Namespace: FlexCel.Core
public Nullable<TChartRelativeRectangle> PositionZeroBased { get; set; }