Such bonds by their terms shall be made payable on or before a date not to exceed twelve years from and after the date of the issuance of such bonds, which latter date may be fixed by resolution or may be fixed by the ordinance confirming the assessment roll. Such bonds to bear interest as may be provided by the ordinance ordering the improvement, not exceeding eight percent per annum, payable as provided in said ordinance, and each bond shall have attached thereto interest coupons for each interest payment. There shall be attached to each bond such number of coupons, not exceeding twelve, as shall be required to represent the interest thereon, payable annually, for the term of said bond. (Prior code § 13.48.070.)