AFAIK those are the numbers. For some there may be OTHERS AS WELL, but those numbers are true for everyone.
"Try to keep your utilization below these numbers, each number is a step 100%, 99%, (95%,) 90%, 75%, 50%, 30%,10%, and from there down."
What is going to happen on my report when utilization goes from 10 to 9 that wont happen when I go from 11 to 10?