Average Top Mid And Bottom

I am needing to do a formula based on a range of data that will return the top third middle third and bottom third.

Example Data
W X Y

Gross Gross
Margin Margin% Rank
51,241 36.46%2
25,584 19.56%20
19,914 16.26%40
17,188 14.27%52
19,167 15.55%43
6,828 5.23%84
48,076 29.17%3
18,282 13.78%47
16,896 12.75%58
16,124 12.14%64
16,549 12.27%59....................

I first need it to look in the rank column for highest number and divide by 3

Then I need it to give me the average Gross Margin if rank is between 1-32, 33-64, 65-95

I have this for the top and bottom but can't get the mid range to work(except it doesn't automatically calculate)

SUMIF($Y$8:$Y$102,"<33",$W$8:$W$102)/32
I have tried averageif....

Using rank to calculate this may not be the most efficent way