; and (B) repay the loan pursuant to the income-based repayment plan under subsection (d). (5) Repayment period For purposes of calculating the repayment period under this subsection, such period shall commence at the time the first payment of principal is due from the borrower. (6) Installments Repayment of loans under this part shall be in installments in accordance with the repayment plan selected under paragraph (1) and commencing at the beginning of the repayment period determined under paragraph (5). (d) Income-Based repayment program (1) In general Notwithstanding any other provision of this Act, the Secretary shall carry out a program under which— (A) a borrower of any loan made under this part (other than a Federal ONE Parent Loan or an Excepted Federal ONE Consolidation Loan) may elect to have the borrower’s aggregate monthly payment for all such loans— (i) not to exceed the result obtained by dividing by 12, 15 percent of the result obtained by calculating, on at least an annual basis, the amount by which— (I) the adjusted gross income of the borrower or, if the borrower is married and files a Federal income tax return jointly with or separately from the borrower’s spouse, the adjusted gross income of the borrower and the borrower's spouse, exceeds (II) 150 percent of the poverty line applicable to the borrower’s family size as determined under section 673(2) of the Community Services Block Grant Act ( 42 U.S.C. 9902(2) ); and (ii) not to be less than $25