the member or his surviving spouse may choose to receive, instead of the benefits of this article, the annuity survivor or disability benefits under the retirement fund law in effect on March 31, 1955. The benefit paid shall be reduced by any payments under the federal Social Security Act. In addition, the member may receive any annuity payments provided by additional annuity contributions.
whichever of subdivision (1) or (2) is larger.
IC 5-10.2-5-1