Okla. Admin. Code § 590:40-9-10
OPERS shall establish Accounts for each Participant to reflect such Participant's Deferred Compensation. Each Account shall be subdivided further and separate records shall be maintained showing the manner in which each Account is invested. Separate records also shall be maintained regarding each Account showing the Deferred Compensation, distributions, and the income, expenses, gains, and losses. All subaccounts are referred to as a Participant's Account. The interest of each Participant shall be the amount in the Account, as determined under 590:40-9-12, plus credits, representing the Participant's Deferred Compensation, profits, income, and other increments attributable to such Deferred Compensation, and minus debits representing the Participant's proportionate share of losses and other decrements or expenses under the Plan and all distributions under the Plan made to or regarding that Participant. These records shall be maintained by the Plan on a calendar quarter-end basis only and available for seven (7) years.
Okla. Admin. Code § 590:40-9-10