Go to Plot Details: Plot Properties: Group tab, set Subgroup Size. This means how many columns/bars will be stacked to become a new column/bar.
Go to Plot Details: Layer Properties: Stack tab, choose Offset to be Cumulative and check Use Subgroup (in Group tab) for Cumulative checkbox.
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Subgrouping in Normal Column Plot
How to:
Within the same dataset: Go to Plot Detail: Plot Properties: Spacing tab, set Subsize Size and Gap Between Subsets(%).
In different dataset: Go to Plot Details: Plot Properties: Group tab, set Subgroup Size. Use increment checkbox indicated to repeat increment list within each subgroup.
