To know the total number of supplemental pages that your site has in Google, simply type in this code.
site:www.yoursite.com *** -view
The normal site:www.domain.com query gives you an idea of all your pages that are in the Google index, which includes supp and non supp pages.
The code I mentioned above will specifically tell you how many pages are in the supp index. If you find that most of your pages are in the supplemental index, it is probably time for you to revamp your site, change its structure so that there are no orphaned pages ( pages which look like they are standing alone without any links to em) and point some good links to your site.