I don't have percentiles for the subtests but I know that with my son's scores all around 140 except his PSI at 109, that puts him in that "rare" DYS category of not having any one score over 145 but being a rare enough profile to have a GAI over 145.
I don't think of him as a 1:10,000 kid but you'd think that he is the way we have to debate, discuss and beg with the school. Some days I feel lucky that is processing speed is "slow" in comparison because we can barely keep up with him as it is. If he has a PSI in the 140 range as well, I'd have likely had a nervous breakdown by now!
If you think about an elementary school teacher with 25 kids in a class, any one teacher will likely NEVER have a kid in the 1:1000 range. I think this is when it seems very, very rare. Looking at a broad populations 1:1000 isn't that big of a deal. But if you look at the one kid in one school with one teacher, it's not nearly as common as the data may suggest.
