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X-Axis: Label always holds a single test entity field with any value.
Y-Axis: It always contains fields with numeric values. Multiple test entity fields on Y-Axis create a stacked chart.
Cross Tab: It helps to create a Group Stacked chart. A simple table only shows the relationship between two variables. Whereas a Cross Tab shows the relationship between two or more variables in the table/chart.
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Once you save the gadget, it will be available in QMetry Custom Gadget > My Gadget tab.