what percent% qaulifies as a grand parent look chart 31.25%

[Officially Retired]

looking at the pedigree statistics some people debate the high percentages as being considered as a grand parent or a heavy contributor of the dog.
just wanting to know everyones thoughts on this subject.
http://www.apbt.online-pedigrees.com...&myPedigrees=1

Very simple:

• Parents = 50%
• Grandparents = 25%
• Great-Grandparents = 12.5%
• Great-Great-Grandparents = 6.25%

If your dog has 31.25% of "X" then X must be both a grand parent and a great-great-grandparent in the pedigree (25% + 6.25% = 31.25%) ... or some similar spread.

Hope this clarifies,

Jack