Generally people will do better on their composite than the average of all 5, because there aren't many people who are going to get 99% on every single section. So you can do lower on a section or two and still be in the top 1% of people overall. What I think is sort of weird is that I've seen people who have the same scores as me, but in different subjects, but our composite is different. For example, I got 90, 92, 96, 95, 69 - total of 442. I've seen other people with, say, 78, 85, 92, 93, 94, which also totals to 442, and they have a composite score of 97, where I got a 95. I didn't think to add up my scaled scores compared to theirs, so maybe that's the difference.