the amount of income tax that was or should have been collected through withholding from Each Class of Income that served as the basis for calculating the person's taxable gross income for 1994 (or, if that Each Class of Income includes occasional income, miscellaneous income, or Ad Hoc Income not falling under miscellaneous income, the amount remaining after deducting the amount of income tax that was or should have been collected through withholding from that income, and, if the person has been issued a refund pursuant to the provisions of Article 9 (Deduction of the Amount of Special Tax Reduction for Salaries or Other Wages Paid to Residents Between January and June 1994) of the Act on Temporary Measures for the Special Tax Reduction of Income Tax for 1994, the amount remaining after deducting the amount of that refund, respectively).