(b) If a participant has started to receive monthly benefit payments on the date of distribution, part of which are attributable to his or her contributions, the value of the lump sum which returns employee contributions is equal to the excess of the amount described in
paragraph (b)(1) of this section over the amount computed in
paragraph (b)(2) of this section.
(1) The amount of accumulated mandatory employee contributions remaining in the plan as of the date of termination plus interest from the date of termination to the date of distribution.
(2) The excess of benefit payments made from the plan between date of plan termination and the date of distribution, over the amount of payments that would have been made if the employee contributions had been paid as a lump sum on the date of plan termination, with interest accumulated on the excess from the date of payment to the date of distribution.