Hi Nithin,
Pie chart is used to show comparison of single vs total entity. Pie chart is best to denote at the highest composite form of a field. As the measures increases, the chart becomes unclear to understand.
1. Select the measure/dimension you want to plot the chart. Click on show me and select the pie chart.
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2. Right click on the field and click on quick table calculation and select percent of total.
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3. After applying quick calculation on field.
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Hope this helps you.
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