Okla. Stat. tit. 19, § 19-1712: Cash surpluses

If and when an actual cash surplus accrues in any fund for any

prior fiscal year, such surplus shall forthwith be transferred to

the same fund for the fiscal year next succeeding the year for which

the taxes were originally levied, and shall be used to pay any

warrants and interest thereon which may be outstanding and unpaid

for such year. After all warrants and interest on such warrants for

such year have been paid or reserved for, the surplus, if any, shall

forthwith be transferred to the next succeeding year for the same

purpose. This procedure shall be followed for each succeeding

fiscal year until all warrants issued prior to the current fiscal

year are paid or reserved for, and then any cash surplus remaining

shall accrue and be transferred to the current fiscal year, to be

used to pay any legal warrant and interest charges of such year.

The term "actual cash surplus", as used herein, is hereby defined to

mean an excess of actual cash actually on hand over and above all

legal obligations. Taxes in process of collection shall not be

considered in determining the actual cash surplus for any fund for

any fiscal year or years.