No. 6% and 76% are both wrong. In reality you should check number of iq catched by ht
Iq 9 and less you means that you can hope to get valuable amount of quality on byregot under excellent condition only
Iq 10 - you will need byregot under good condition an will get near 50%
Iq 11 - you may hope to get 50% and more with byregot under normal condition. Check quality progress - 12% and more will mean 60%, 15% - 80... These numbers are very approx.