How to show static line?

Question

Hi all, I try to put Two Vertical Bar and One fixes line = value 500
!http://img291.imageshack.us/img291/2725/graphsubir.png!
chart:
<Graph graphType="BAR_VERT_CLUST2Y" depthAngle="50" depthRadius="8" pieDepth="30" pieTilt="20" seriesEffect="SE_AUTO_GRADIENT"><LegendArea visible="true"/>
<SeriesItems>
<Series id="0" markerType="MT_BAR" color="#ff0000"/>
<Series id="1" markerType=" MT_BAR" color="#99ccff"/>
<Series id="2" markerType="MT_MARKER" color="#ff0000" lineStyle="LS_SOLID"/>
</SeriesItems>
<PlotArea fillColor="#ffff33"/>
<LegendArea position="LAP_TOP"/>
<LegendText>
<GraphFont name="Arial" fontColor="#000000" size="14" />
</LegendText>
<Title text="" visible="true" horizontalAlignment="CENTER"/>
<LocalGridData colCount="{count(xdoxslt:group(.//ROW, 'saw_2'))}" rowCount="2">
<RowLabels><Label>Valor Obtenido</Label><Label>Valor Previsto</Label></RowLabels>
<ColLabels>
<xsl:for-each-group xmlns:xsl="http://www.w3.org/1999/XSL/Transform" select=".//ROW" group-by="saw_2">
<xsl:sort select="current-group()/saw_2"/>
<Label>
<xsl:value-of select="current-group()/saw_2"/>
</Label>
</xsl:for-each-group>
</ColLabels>
<DataValues>
<RowData>
<xsl:for-each-group xmlns:xsl="http://www.w3.org/1999/XSL/Transform" select=".//ROW" group-by="saw_2">
<xsl:sort select="current-group()/saw_2"/>
<Cell>
<xsl:value-of select="sum(current-group()/saw_3)"/>
</Cell>
</xsl:for-each-group>
</RowData>
<RowData>
<xsl:for-each-group xmlns:xsl="http://www.w3.org/1999/XSL/Transform" select=".//ROW" group-by="saw_2">
<xsl:sort select="current-group()/saw_2"/>
<Cell>
<xsl:value-of select="sum(current-group()/saw_4)"/>
</Cell>
</xsl:for-each-group>
</RowData>
<RowData>
<xsl:for-each-group xmlns:xsl="http://www.w3.org/1999/XSL/Transform" select=".//ROW" group-by="saw_2">
<xsl:sort select="current-group()/saw_2"/>
<Cell>
500
</Cell>
</xsl:for-each-group>
</RowData>
</DataValues>
</LocalGridData>
</Graph>
thanks for request

Answer 1

add the following
Your code is this
<SeriesItems>
<Series id="0" markerType="MT_BAR" color="#ff0000"/>
<Series id="1" markerType=" MT_BAR" color="#99ccff"/>
<Series id="2" markerType="MT_MARKER" color="#ff0000" lineStyle="LS_SOLID"/>
</SeriesItems>
Add the following after this
<Y1ReferenceLine>
<ReferenceLine index="0" visible="true" lineWidth="2" text="ref line " value="500.0" displayedInLegend="true" lineColor="#ff11"/>
</Y1ReferenceLine>
again your code