Pub. Util. Code, § 50231

The ordinance calling a special bond election shall fix the date on which the election will be held, and the manner of holding the election and of voting for or against incurring the indebtedness. It shall also recite the objects and purposes for which the indebtedness is proposed to be incurred, the estimated cost of the transit facilities, works, lands, structures, rights, equipment, or other property proposed to be acquired, constructed, or completed, the amount of the principal of the indebtedness to be incurred therefor, and the maximum rate of interest to be paid on the indebtedness, which shall not exceed 6 percent per annum, payable semiannually or annually the first year and thereafter semiannually.