Any loan made under section 636a ¹ of this title and section 4452 ¹ of title 42 shall not exceed the current cost of repairing or replacing the disaster injury, loss, or damage in conformity with current codes and specifications. Any loan made under sections 636a ¹ and 636d of this title, and sections 3538 and 4452 ¹ of title 42 shall bear interest at a rate determined by the Secretary of the Treasury, taking into consideration the current average market yield on outstanding marketable obligations of the United States with remaining periods to maturity of ten to twelve years reduced by not to exceed 2 per centum per annum. In no event shall any loan made under this section bear interest at a rate in excess of 6 per centum per annum.