 
     taxable_income = Decimal.sub(total_cash, total_relief)
 
-    # TODO: depending on month route tax calculation to appropriate functions
-    tax_ded = gra_income_tax(taxable_income, "2019")
+    tax_ded = gra_income_tax(taxable_income, tax_year)
 
     overtime_tax = gra_overtime_tax(emp.overtime_earned, earned_salary)
 

    end
  end

  defp gra_income_tax(i, "2019") do
    decimal_1 = Decimal.new("1")

    cond do

  end

  ### Private Functions ###
  defp parse_payroll_record(list, employees, tax_year) do
    [
      month,
      id,
