There is hereby created a surplus and deficiency fund to be used as provided in this chapter and in section 11.8 of the charter. When all outstanding bonds of an improvement district have been paid and any monies remain to the credit of the district, they shall be transferred to the special surplus and deficiency fund. Whenever there is a deficiency in any improvement district fund to meet the payment of outstanding bonds and interest due thereon, the deficiency shall be paid out of said surplus and deficiency fund. (Ord. 9, Series 1988)