Is it possible to know how much disk space each project in a SubVersion repository is using?

I can check out a working copy of each project and look at the size each project takes up, but I don't think that encompasses the total size of the project (all revisions).

I can look under the "db" directory of the repository, but none of the files in there make sense - I don't think it is possible to use them to figure out how much space each project occupies.

I tried the svn ls --verbose command, but the size that it gives me is just the size of the actual files in the head revision, I don't think it includes all revisions.

Maybe this isn't possible, but I thought I would ask.

Thanks in advance!