Mimi,
The only way of doing this without a VBA routine is to export the information to Excel and graph it there. Create a project filter and apply it on the Mapping dialog box during creation of the export map. Since you have a resource pool,
the export must be performed from there, unless you want to do it on each project.
Gregg D. Richie, PMP, MCTS; Author, Microsoft Project 2010, Microsoft Official Academic Course Series