The Tax Prepayment calculation base for 1965 as determined under the preceding paragraph for a Resident who had, among the dependents who served as the basis for calculating the taxable aggregate income and similar amount for income tax for 1964, dependents who were 12 years of age as of December 31, 1964 is to be the amount obtained by deducting, from the amount calculated pursuant to that paragraph, the total of the amounts calculated by multiplying the per-person deduction amount set forth in column B of Appended Table 1 of the Supplementary Provisions according to that taxable aggregate income and similar amount by the number of those dependents.