Sunil:
--If you only want totals for Salary, then just put Salary in the "Total of" Role.
-- Do not put any variable under the "Subtotal of" Role.
--Then just put your 2 variables Dept and Sub-Dept under the "Group Analysis By" role.
This should give you just one subtotal for each Sub-Dept EXCEPT at the very bottom where you should see a total line for Sub-Dept, then a total line for Dept, then an OVERALL total line.
In order to selectively get subtotals, you'd have to move beyond the LIST DATA task and into the world of PROC REPORT. At the present time, PROC REPORT can only be submitted via a code node. (In the future, there are plans for a GUI interface to PROC REPORT in EG.)
If you cannot get the LIST data task working the way you want or if you need help with a PROC REPORT solution, your best bet is to contact SAS Tech Support.
cynthia