Okla. Stat. tit. 70 § 5-115b
Upon the expiration of the term of office, the treasurer shall deliver check or warrant registers to the succeeding treasurer, and each successor in office shall act as though check or warrant entries were registered by the successor, who shall continue registration of all district checks or warrants. If a check or warrant cannot be paid for want of sufficient funds, a district may enter into an agreement not to extend beyond the current fiscal year with the depository bank to honor payment of these checks at an annual rate of interest as negotiated by the district and depository bank, which shall not exceed a rate equal to five percent (5%) above the average United States Treasury Bill rate of the preceding calendar year as determined by the State Treasurer on the first regular business day of each year.
Okla. Stat. tit. 70, § 5-115b