Hello Sandra,
With the current release of the financial reporter, there is a really fast way to sum non-contiguous departments. Drag the account group you want to analyze onto the sheet, and select "Departmental Comparative" from the format box. Choose the dpartments you want, and then select, "Sum selected departments", giving the resulting column an appropriate title. If you don't want the individual departments to show on your output sheet, then mark the columns "hide when print".