No person having a husband, wife, child, or descendant or parent, shall, by his or her last will and testament, devise or bequeath to any benevolent, charitable, literary, scientific, religious or missionary society, association, corporation or purpose, in trust or otherwise, more than one-half part of his or her estate, after the payment of his or her debts, and such devise or bequest shall be valid to the extent of one-half, and no more. The validity of a devise or bequest for more than such one-half may be contested only by a surviving husband, wife, child, descendant or parent. When payment of a devise or bequest to such society, association, corporation or purpose is postponed, in computing its one-half part, no allowance may be made for such postponement or for any interest or gains or losses which may accrue after the testator's death. The value of an annuity or life estate, legal or equitable, shall not be computed upon the actual duration of the life, but shall be computed upon the actuarial value according to the American Experience Table of Mortality at the rate of four per centum per annum. Such value shall be deducted from the fund or property, which is subject to the annuity or life estate, in order to ascertain the value of a future estate or remainder interest passing to such society, association, corporation or purpose.