In order to bring the sinking fund for each issue of term bonds up to the proper amortization basis, the deficiency as shown by the final tabulation and calculation shall be raised and paid into a fund, to be known as the special sinking fund, in annual installments at the rate of not less than one-fifth of a mill on the dollar of the last corrected valuation of taxable property in the municipality, county or school district, as the case may be, until the deficiency with interest compounded annually at three and one-half per cent from January first, one thousand nine hundred and seventeen, is accumulated.