How to: Edit a graph in a PowerPoint slide.
Solution:
Select the graph to be edited, select the 'Edit' menu and select 'Chart Object', and select 'Edit' from the submenu.
1) Select (single-click) the desired graph object. (Handles appear around the border.)
2) Select the 'Edit' menu and select 'Chart Object'. (A submenu appears.)
3) Select 'Edit' from the 'Chart Object' submenu. (The graph application window appears with the menus and toolbar tools active.)
4) Select the 'View' menu and select 'Datasheet'. (The <x> Datasheet appears.)
(Where <x> is the active presentation).
5) Make any desired changes to the datasheet.
NOTE: Changes made to the datasheet will automatically display on the graph.
6) Click outside the graph, to exit the graph application and return to the active PowerPoint presentation.
NOTE: Other changes can be made to the graph while in the graph application editing window.