telerik html chart ScatterLineSeries not support DataFieldX DataFieldY

i want use htmlchart in my asp.net project i use VS 2012 and i wrote below code
but DataFieldX and DataFieldY not support in my page and when i open page i see Parser Error


<telerik:RadAjaxManager ID="RadAjaxManager1" runat="server">
</telerik:RadAjaxManager>
<telerik:RadStyleSheetManager ID="RadStyleSheetManager1" runat="server">
</telerik:RadStyleSheetManager>

<TooltipsAppearance BackgroundColor="White" DataFormatString="{1}% in {0} minutes"></TooltipsAppearance>
<LabelsAppearance Visible="false">
</LabelsAppearance>
</telerik:ScatterLineSeries>
<telerik:ScatterLineSeries Name="1.6C" DataFieldX="ChargeTime16C" DataFieldY="ChargeCurrent16C">
<TooltipsAppearance BackgroundColor="White" DataFormatString="{1}% in {0} minutes"></TooltipsAppearance>
<LabelsAppearance Visible="false">
</LabelsAppearance>
</telerik:ScatterLineSeries>
<telerik:ScatterLineSeries Name="3.1C" DataFieldX="ChargeTime31C" DataFieldY="ChargeCurrent31C">
<TooltipsAppearance BackgroundColor="White" DataFormatString="{1}% in {0} minutes"></TooltipsAppearance>
<LabelsAppearance Visible="false">
</LabelsAppearance>
</telerik:ScatterLineSeries>
</Series>
<XAxis>
<LabelsAppearance DataFormatString="{0}m" />
<TitleAppearance Text="Time" />
</XAxis>
<YAxis MaxValue="100">
<LabelsAppearance DataFormatString="{0}%" />
<TitleAppearance Text="Charge" />
</YAxis>
</PlotArea>
<ChartTitle Text="Charge current vs. charge time">
</ChartTitle>
</telerik:RadHtmlChart>
</div>