Do you have the swap space data now, if so how are you collecting that?
To get the total size you are going to need a custom SQL Query that adds up the space in the query.
I am making a couple of assumptions here, so this may not be 100% what you're looking for...
NPM allocates a "Volume Type" which includes "Fixed Disk", "Virtual Memory" and "RAM" (they are the 3 my setup generates.) If you do a report that does a SUM on the volume size, and includes the Volume Type as a field you end up with something that is hopefully getting you in the right direction. It doesn't format exactly how you want it to, but the attached report should give you something to start from.
Of course, it'll only include the sizes of volumes that are being monitored by NPM, so if a volume exists but you don't monitor, it won't appear in the size reported by this report.