I wouldn't worry too much about these. Lots of dogs get 'fatty lumps' as they get older, my girl is 9 too and she's just got her first two. They are usually nothing to worry about, and vary in size.
If you are worried though, ask your vet if he'll have a look. Most will do bloodtests just to check for any signs of cancer, but I would say most of the time, they are just harmless cysts.