§ 28. “Unallocated interest fund” defined

As used in this Act [sections 1 to 6, 7 to 39, and 41 to 44 of this Appendix], the term “unallocated interest fund” means the sum of
(1) the earnings and profits accumulated prior to March 4, 1923, and attributable to investments and reinvestments under section 12 [section 12 of this Appendix] by the Secretary of the Treasury, plus
(2) the earnings and profits accumulated on or after March 4, 1923, in respect of the earnings and profits referred to in clause (1) of this section.