Okla. Stat. tit. 15, § 15-262: Repayment must be made in current funds

Except when the parties otherwise expressly agree in writing, a

borrower of money must pay the amount due in such money as is

current at the time when the loan becomes due, whether such money is

worth more or less than the actual money lent.

R.L. 1910, § 1000. Amended by Laws 1996, c. 56, § 29, emerg. eff.

April 8, 1996.