The formula is based upon the bottom of the bands, and checks from the value in the first arrayup, and below the next band, returning the corresponding value in the second array. So with
=LOOKUP(C2,{0,0.7,0.8,0.9,1,1.25,1.5},{0,0.05,0.06,0.07,0.1,0.12,0.15})
if C2 has a value between 0 and less than 0.7, the formula returns 0.
From 0.7 and less than 0.8, it returns 0.05 or 5%, etc.
Just plug the formula in a cell, format it as a perecentage, and change C2 and see what yoy get.
You can send me a workbook if you like and I will see what I can do.
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