The following benefit shall be payable to the survivors of an annuitant or to the survivors of a member whose death occurs after termination of service for any cause if on the date of termination of service, the member had at least 20 years of creditable service and if the annuitant or member had made contributions for the purposes of this Section for at least one year of creditable service after July 24, 1959:
(1) Where the member's death occurs on or after July 1, 1990, a beneficiary designated by the member shall be entitled to receive, in a single sum, an amount equal to the member's highest annual rate of salary within the last 4 years of service, reduced by 1/6 of that annual salary for each year or fraction thereof that has elapsed between the date of retirement or termination of service and the date of death, but subject to a minimum payment equal to 1/6 of that annual salary, the actual contributions made by the member for survivor benefits, not including interest thereon, or $3,000, whichever is the greatest. If no beneficiary is designated by the member or if no designated beneficiary survives the member, the lump sum benefit under this paragraph shall be paid to the eligible dependent beneficiary or to the trust established for such eligible dependent beneficiary, as determined under Section 16-140 (3), or, if there is no dependent beneficiary, to the decedent's estate upon receipt of proper proof of death.(2) In lieu of the benefit under paragraph (1) of this Section, a dependent beneficiary may receive the benefits provided under subsection (b) of Section 16-141. This paragraph (2) is inapplicable where a non-dependent beneficiary designated by a member survives the member.(3) Notwithstanding the creditable service limitations contained elsewhere in this Section and under paragraph (3) of Section 16-143, a surviving dependent beneficiary of an annuitant whose death occurs after December 31, 1981, may receive only the benefits provided in subsection (b) of Section 16-141, subject to a maximum benefit of $200 per month.