Could someone please help me make sense of the table in this link:

http://www.hoagiesgifted.org/highly_profoundly.htm

I see this article referenced a lot, and I find it confusing. It looks like the threshold for PG is a lot higher when the extended norms are used? So a kid who gets 152 but doesn't hit any ceilings is profoundly gifted, but a kid who gets 160 but hits ceilings is EG? Is it just a difference in how people name it? Is there an accepted convention for where EG or PG begins?

Thanks.