[Evolution] Evolution backups: is there a max size of the evolution-backup-20171231.tar.gz file

[glenn <temp1 blepsias net>]

Hi all- 
My Evolution backup appear to be topping out at 7.7 gb in size. Is this
a maximum size for the produced evolution-backup-20171231.tar.gz file? 

I've been using Evolution since the Ximian days: some of the items in
my backups stretch back to that era. Happy New Years. Glenn