Collapsing a subpanel leaves just the header on display
and allows additional subpanels, if any, to be displayed in the workspace.
If a subpanel is collapsed, only the subpanel heading is displayed.
Expanding the subpanel displays the data rows and columns again.
A down arrow in the left corner of a subpanel header indicates that the subpanel can be collapsed.
Collapsing the subpanel turns the down arrow into a right arrow (see Figure 1).
To collapse a subpanel,
set your cursor on the down arrow and press Enter. To expand a subpanel, set your cursor on the right
arrow and press Enter.
Figure 1. Workspace with collapsed subpanel
If a collapsed subpanel contains no data, the text No Data will be displayed in the
right corner of the title bar. In some collapsed subpanels that contain no data, the subpanel title
might be replaced by explanatory text.
in the left corner of a subpanel header indicates that the subpanel can be collapsed.
Collapsing the subpanel turns the down arrow into a right arrow 
(see Figure 1).