Add average line to bar chart (table & matrix)

Result:

Mark the SVG measure below as Image URL：

chart = 
VAR Max_Value = MAXX ( ALLSELECTED ('table'),[KPI] )
VAR Avg_Value = AVERAGEX ( ALLSELECTED ('table'),[KPI] )
VAR SVG ="
    data&colon;image/svg+xml;utf8,
    <svg xmlns='http://www.w3.org/2000/svg' width='150' height='30'>
    <g>
        <title>公众号wujunmin</title>
        <rect x='0' y='5' width='"
            & 150 * [KPI] / Max_Value & "' height='20' 
            fill='deepskyblue'
        /> 
        <line x1='" & 150 * Avg_Value / Max_Value & "'
            x2='" & 150 * Avg_Value / Max_Value & "'
            y1='0' y2='30' 
            stroke-width='1' stroke='black' stroke-dasharray='5'
        />
    </g>
    </svg>"
RETURN
    SVG