Fund Balance Law and Legal Definition
"Fund balance means the current net assets of the Fund available for payment of benefits, as determined by the Office in accordance with appropriate accounting standards, but does not include any amount attributable to--
(A) the Federal Employees' Retirement System; or
(B) contributions made under the Federal Employees' Retirement Contribution Temporary Adjustment Act of 1983 by or on behalf of any individual who became subject to the Federal Employees' Retirement System.” (5 USCS § 8331)