Would it matter whether it is 82.3 or 83? It is a ridiculously high number when it crosses 80%.
It means Stanford keeps accepting fewer and fewer people in order to reach their target matriculant size.
On a side note, it would be wrong for someone to choose college because the yield is very high there. OTOH, the yield is very high mainly because the matriculants as well as applicants believe it is the best college for them.