Each year, after this Act becomes fully operative, and until all of the bonds issued as herein provided have been retired, there is levied a direct annual tax upon all real and personal property in this State subject to taxation for such amount as shall be necessary and sufficient to pay the interest annually, as it shall accrue, on all bonds issued under the provisions of this Act and also to pay and discharge the principal of such bonds at par value, as such bonds fall due; and the amounts of such direct annual tax shall be appropriated for that specific purpose.
     The proceeds of this tax shall be paid into the Universities Building Bond Retirement and Interest Fund in the State treasury.
     The required rate of such direct annual tax shall be fixed each year by the officers charged by law with fixing the rate for State taxes on the valuation of real and personal property in this State subject to taxation in accordance with the provisions of the statutes in such cases: provided, however, that if money has been transferred from the General Revenue Fund to the Universities Building Bond Retirement and Interest Fund for the same purpose for which said direct annual tax is levied and imposed then said officers shall in fixing the rate of said direct annual tax make proper allowance in the amount of money so transferred in reduction of the tax levied under this Section and the tax levied under this Section shall be abated in that amount.