bonus calculation

Hello

im seeking some guidance and help from the pros in bonus calculation. i have attached a workbook. it has 2 worksheets that matter for this.

-ISE bonus and commission
-bonus %

basically, i have the rev. and budget, so i have calculated their simple % to their budget(rev/budget).

now i.e. if that percentage is 81%, then lookup bonus sheet, see criteria (<90% is $0 payout, so G8 in "ise bonus and comission" worksheet should equal that number.

if someone can provide me with some help as there bonus can be between 100-100% etc. i have highlighted the cell in yellow and the again the bonus criteria is on "bonus worksheet".
i really appreciate the help!