The surviving spouse may elect to take an elective share of an estate subject to election as follows:
(1) If there is surviving issue, the elective share shall equal one-third of the value of the estate subject to election, reduced by the value of all spousal benefits; or
(2) If there is no surviving issue, the elective share shall equal one- half of the value of the estate subject to election, reduced by the value of all spousal benefits.