Indicates how summaries are displayed inside groups.
The group header is rendered as cells and summary values are rendered inside the cells aligned with their column.
Group summaries are displayed in a flat list in the spanning group header.
No summaries are displayed in the group.
Group summaries are displayed as summary rows at the bottom of the group.
Group summaries are displayed as summary rows at the top of the group.
Indicates how summaries are displayed inside groups.