I'm trying to calculate a new sales commission based upon a range possible
values.

Sales Rep earns a different commission based upon Margin % on the sale.

A simple version table is this:
From Until
0.0% 2.99% 0.00%
3.0% 9.99% 1.00%
10.0% 14.99% 1.25%
15.0% 19.99% 1.75%
20.0% 25.99% 2.50%
26.0% 3.25%

(The actual table is much more detailed and does not work using Vlookup)