Okla. Stat. tit. 70, § 70-135a: Office created - Reimbursement of county

In each county having a population of not less than thirteen

thousand (13,000) nor more than twenty thousand (20,000) according

to the 1960 and each succeeding Federal Decennial Census and a

valuation of not more than Twelve Million Dollars ($12,000,000.00)

tangible properties, not including valuation of homestead exemptions

allowed in any year, there is hereby created in the office of the

county treasurer of each county, in addition to all other deputies

authorized or provided by law, a deputy for school accounts, for

whose salary the county shall be reimbursed out of the surplus

revenues of the school districts heretofore served wholly at county

expense and whose accounts and funds are kept by and under

responsibility of the county treasurer, which reimbursement shall be

in the manner hereinafter provided.