Non-Taxable Salary Component

Hello Everyone,
In creating the salary components, i created a deduction called SSF 5.5% which is supposed to be deducted from total earnings before tax is applied (Exempted from IncomeTax Check box has been checked). Unfortunately, the tax is computed on the total earnings without deducting the SSF 5.5%. Please help.

Please provide information on how other taxes are configured. Are you using tax slab or custom calculations for your other taxes?