Whole life insurance pays a pre-determined benefit either at or soon after the insured's death. The symbol "(x)" is used to denote "a life aged "x"" where "x" is a non-random parameter that is assumed to be greater than zero. The actuarial present value of one unit of whole life insurance issued to "(x)" is denoted by the symbol formula_1 or formula_2 in actuarial notation. Let "G>0" (the "age at death") be the random variable that models the age at which an individual, such as "(x)", will die. And let "T" (the future lifetime random variable) be the time elapsed between age-"x" and whatever age "(x)" is at the time the benefit is paid (even though "(x)" is most likely dead at that time). Since "T" is a function of G and x we will write "T=T(G,x)". Finally, let "Z" be the present value random variable of a whole life insurance benefit of 1 payable at time "T". Then: