The total principal amount of new loans made and installments paid pursuant to lines of credit (as defined in section
1085 of this title) to students covered by Federal loan insurance under this part shall not exceed $2,000,000,000 for the period from July 1, 1976, to September 30, 1976, and for each of the succeeding fiscal years ending prior to October 1, 2014. Thereafter, Federal loan insurance pursuant to this part may be granted only for loans made (or for loan installments paid pursuant to lines of credit) to enable students, who have obtained prior loans insured under this part, to continue or complete their educational program; but no insurance may be granted for any loan made or installment paid after September 30, 2018.