In the current version of RadControls it is not possible to display labels for SeriesItems having YValue of 0 for BarSeries, ColumnSeries, PieSeries and DonutSeries. This limitation is due to visual considerations of the RadHtmlChart.
However, I have logged your idea in our feedback portal here
, so that you can monitor, comment or vote on it, in order to raise its priority. If this idea gets enough votes our developers might consider its implementation in the future.
I have also updated your Telerik points for sharing your feedback with us.
the Telerik team
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