On and after October 1, 1984, any amount which (but for this section) would have been transferred to the Railroad Retirement Account pursuant to paragraph (2) or (4) of section 231f(c) of this title shall be transferred to the Social Security Equivalent Benefit Account. On and after October 1, 1984, no transfer shall be made to the Railroad Retirement Account pursuant to paragraph (2) or (4) of section 231f(c) of this title.

To the extent that the authorization for appropriation contained in section 231n(b) of this title is attributable to the cost of social security equivalent benefits, on and after October 1, 1984, any reference in such section to the Railroad Retirement Account shall be treated as a reference to the Social Security Equivalent Benefit Account.

Amounts appropriated or transferred to the Social Security Equivalent Benefit Account under this section shall be credited or transferred to such Account at the same time and in the same manner as such amounts would have been credited or transferred to the Railroad Retirement Account but for this section.

Except as otherwise provided in this section, amounts in the Social Security Equivalent Benefit Account shall be available only for purposes of paying social security equivalent benefits under this subchapter and to provide for the administrative expenses of the Board allocable to social security equivalent benefits. The Secretary shall from time to time transfer to the disbursing agent under section 231f(b)(4) of this title amounts necessary to pay those benefits.

On and after October 1, 1984, any transfer which (but for this paragraph) would be required to be made from the Railroad Retirement Account under paragraph (2) or (4) of section 231f(c) of this title shall be made from the Social Security Equivalent Benefit Account.

Whenever the Board finds that the balance in the Social Security Equivalent Benefit Account will be insufficient to pay social security equivalent benefits which it estimates are due in any month, it shall request the Secretary of the Treasury to transfer from the Railroad Retirement Account to the credit of the Social Security Equivalent Benefit Account such moneys as the Board estimates will be necessary for the payment of such benefits, and the Secretary shall make such transfer.

Upon establishment of the National Railroad Retirement Investment Trust and from time to time thereafter, the Board shall direct the Secretary of the Treasury to transfer, in such manner as will maximize the investment returns to the Railroad Retirement system, the balance of the Social Security Equivalent Benefit Account not needed to pay current benefits and administrative expenses required to be paid from that Account to the National Railroad Retirement Investment Trust or the Railroad Retirement Account, and the Secretary shall make that transfer. Any balance transferred under this paragraph shall be used by the National Railroad Retirement Investment Trust or the Railroad Retirement Board only to pay benefits under this subchapter or to purchase obligations of the United States (either directly or through a commingled account consisting only of such obligations) that are backed by the full faith and credit of the United States pursuant to chapter 31 of title 31. The proceeds of sales of, and the interest income from, such obligations shall be used by the Trust only to pay benefits under this subchapter or to purchase such additional obligations.

For purposes of making payments of social security equivalent benefits, references in the 1 subchapter to the Railroad Retirement Account shall be treated as references to the Social Security Equivalent Benefit Account.

For purposes of this section, the term “social security equivalent benefits” means benefits payable under this subchapter which are of a kind taken into account in determining the amount of transfers made under section 231f(c)(2) of this title.