If the number of data labels is greater than what can be accommodated in the available space, then the data labels are either truncated (with ellipses to indicate truncation), wrapped, or rotated. Ellipses are added automatically when the label overflows beyond a predefined length. In any of these cases, the complete label is still visible to your user in the tooltip.
Due to the flexibility of format selection and the limitations of automation there may still be instances where label overlapping will occur, if increasing the size of the chart is not an option, it will still be possible to override the default smart label management format by selecting the Slant labels option from the Results Analayzer’s Display Options.